Organic light emitting display device

ABSTRACT

Disclosed is an organic light emitting display device including an encapsulation layer covering a pixel array layer provided on a substrate and a cover window coupled to a touch sensing layer. The touch sensing layer may include a first touch electrode layer provided on the encapsulation layer, a second touch electrode layer provided on the first touch electrode layer, and a pressure reaction member provided between the first touch electrode layer and the second touch electrode layer. Electrical characteristic of the pressure reaction member may be changed according to force applied to the pressure reaction member.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of Republic of Korea PatentApplication No. 10-2016-0127165 filed on Sep. 30, 2016, which is herebyincorporated by reference as if fully set forth herein.

BACKGROUND Related Field

One or more embodiments disclosed herein relate to an organic lightemitting display device including a touch panel.

Discussion of the Related Art

A touch panel is a type of input device, which is applied to an imagedisplay device such as liquid crystal display (LCD) device, fieldemission display (FED), plasma display panel (PDP), electroluminescentdisplay (ELD), electrophoretic display (EPD), organic light emittingdisplay device, etc., and enables a user to input information bydirectly touching a screen with a finger, a pen, or the like whilelooking at the screen of the image display device.

Recently, the touch panels are used as input devices of various productssuch as televisions (TVs), notebook computers, monitors, etc., inaddition to portable electronic devices such as electronic notebooks,e-books, portable multimedia players (PMPs), navigation devices,ultra-mobile personal computers (UMPCs), mobile phones, smartphones,smartwatches, tablet personal computers (PCs), watch phones, mobilecommunication terminals, etc.

Recently, as a user interface environment such as applications requiringtouch information about a force touch is established, organic lightemitting display devices for sensing the force touch are beingresearched and developed. For example, WO 2010/026515 discloses anorganic light emitting diode (OLED) device including a capacitiveproximity sensing means that senses a force touch of a user by sensing avariation of a capacitance caused by a user touch through a mechanicalelement disposed between an OLED means and a mounting structure.However, in the OLED device of the related art, a thickness increasesdue to the mechanical element disposed between the OLED means and themounting structure.

SUMMARY

An organic light emitting display device disclosed herein substantiallyobviates one or more problems due to limitations and disadvantages ofthe related art.

Advantageously, an organic light emitting display device includes atouch panel and has a thin thickness.

In addition, an organic light emitting display device integrated with atouch panel senses a touch position and a touch force.

Additional advantages and features of the invention will be set forth inpart in the description which follows and in part will become apparentto those having ordinary skill in the art upon examination of thefollowing or may be learned from practice of the invention. Theobjectives and other advantages of the invention may be realized andattained by the structure particularly pointed out in the writtendescription and claims hereof as well as the appended drawings.

In one or more embodiments, an organic light emitting display deviceincludes an encapsulation layer covering a pixel array layer provided ona substrate and a cover window coupled to a touch sensing layer, whereinthe touch sensing layer includes a first touch electrode layer providedon the encapsulation layer, a second touch electrode layer provided onthe first touch electrode layer, and a pressure reaction member betweenthe first touch electrode layer and the second touch electrode layer,electrical characteristic of the pressure reaction member changedaccording to force applied to the pressure reaction member. The pressurereaction member may include a piezoelectric material or a piezoresistivematerial.

In one or more embodiments, an organic light emitting display devicecomprises: a display layer including: a substrate, a pixel array layeron the substrate, the pixel array layer including a plurality of pixels,each of the plurality of pixels including a thin film transistor (TFT)and an organic light emitting diode, and an encapsulation layer coveringthe pixel array layer; a cover window; and a touch sensing layerdirectly disposed on the display layer, the touch sensing layer disposedbetween the display layer and the cover window. The touch sensing layermay comprise: a first touch electrode layer directly on the displaylayer, a second touch electrode layer between the first touch electrodelayer and the cover window, and a pressure reaction member between thefirst touch electrode layer and the second touch electrode layer,electrical characteristic of the pressure reaction member changedaccording to force applied to the pressure reaction member.

In one or more embodiments, the organic light emitting display devicefurther comprises a touch driving circuit configured to determine forceof a touch on the cover window according to a change in the electricalcharacteristic of the pressure reaction member associated with thetouch.

In one or more embodiments, the pressure reaction member comprises apiezoelectric material or a piezoresistive material. The piezoelectricmaterial may comprise at least one of lead zirconate titanate (PZT),BaTiO₃, polyvinylidene difluoride (PVDF), and parylene-C. Thepiezoresistive material may comprise a polymer and a conductive filler.The conductive filler may comprise at least one of nickel (Ni), copper(Cu), silver (Ag), aluminum (Al), iron (Fe), vanadium oxide (V₂O₃),titanium oxide (TiO), carbon black, graphite, graphene, and carbon nanotube (CNT).

It is to be understood that both the foregoing general description andthe following detailed description of the present invention areexemplary and explanatory and are intended to provide furtherexplanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this application, illustrate embodiments of the invention andtogether with the description serve to explain the principle of theinvention. In the drawings:

FIG. 1 is a cross-sectional view for describing an organic lightemitting display device according to an embodiment;

FIG. 2 is a diagram for describing a configuration of a touch sensinglayer illustrated in FIG. 1;

FIG. 3 is a cross-sectional view taken along line I-I′ illustrated inFIG. 2;

FIG. 4 is a graph for describing a resistance variation caused bypressure applied to a pressure reaction member illustrated in FIG. 2;

FIGS. 5A and 5B are cross-sectional views for describing a drivingmethod of an organic light emitting display device according to anembodiment;

FIG. 6 is a diagram illustrating a modification example of a touchsensing layer in an organic light emitting display device according toan embodiment;

FIG. 7 is a cross-sectional view for describing an organic lightemitting display device according to another embodiment;

FIG. 8 is a cross-sectional view for describing an organic lightemitting display device according to another embodiment;

FIG. 9 is a cross-sectional view for describing an organic lightemitting display device according to another embodiment;

FIG. 10 is a diagram for describing a touch sensing layer illustrated inFIG. 9;

FIG. 11 is a cross-sectional view for describing an organic lightemitting display device according to an embodiment;

FIG. 12 is a diagram for describing a configuration of a touch sensinglayer illustrated in FIG. 11;

FIG. 13 is a cross-sectional view taken along line II-II′ illustrated inFIG. 12;

FIGS. 14A and 14B are cross-sectional views for describing a drivingmethod of an organic light emitting display device according to anotherembodiment;

FIG. 15 is a cross-sectional view for describing an organic lightemitting display device according to another embodiment;

FIG. 16 is a cross-sectional view for describing an organic lightemitting display device according to another embodiment;

FIG. 17 is a cross-sectional view for describing an organic lightemitting display device according to another embodiment; and

FIG. 18 is a flowchart for describing a touch sensing method performedby an organic light emitting display device according to an embodiment.

DETAILED DESCRIPTION

Reference will now be made in detail to the exemplary embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings. Wherever possible, the same reference numbers will be usedthroughout the drawings to refer to the same or like parts.

Advantages and features of the present invention, and implementationmethods thereof will be clarified through following embodimentsdescribed with reference to the accompanying drawings. The presentinvention may, however, be embodied in different forms and should not beconstrued as limited to the embodiments set forth herein. Rather, theseembodiments are provided so that this disclosure will be thorough andcomplete, and will fully convey the scope of the present invention tothose skilled in the art. Further, the present invention is only definedby scopes of claims.

A shape, a size, a ratio, an angle, and a number disclosed in thedrawings for describing embodiments of the present invention are merelyan example, and thus, the present invention is not limited to theillustrated details. Like reference numerals refer to like elementsthroughout. In the following description, when the detailed descriptionof the relevant known function or configuration is determined tounnecessarily obscure the important point of the present invention, thedetailed description will be omitted.

In a case where ‘comprise’, ‘have’, and ‘include’ described in thepresent specification are used, another part may be added unless ‘only˜’is used. The terms of a singular form may include plural forms unlessreferred to the contrary.

In construing an element, the element is construed as including an errorrange although there is no explicit description.

In describing a position relationship, for example, when a positionrelation between two parts is described as ‘on˜’, ‘over˜’, ‘under˜’, and‘next˜’, one or more other parts may be disposed between the two partsunless ‘just’ or ‘direct’ is used.

In describing a time relationship, for example, when the temporal orderis described as ‘after˜’, ‘subsequent˜’, ‘next˜’, and ‘before˜’, a casewhich is not continuous may be included unless ‘just’ or ‘direct’ isused.

It will be understood that, although the terms “first”, “second”, etc.may be used herein to describe various elements, these elements shouldnot be limited by these terms. These terms are only used to distinguishone element from another. For example, a first element could be termed asecond element, and, similarly, a second element could be termed a firstelement, without departing from the scope of the present invention.

A first horizontal axis direction, a second horizontal axis direction,and a vertical axis direction should not be construed as only ageometric relationship where a relationship therebetween is vertical,and may denote having a broader directionality within a scope whereelements of the present invention operate functionally.

The term “at least one” should be understood as including any and allcombinations of one or more of the associated listed items. For example,the meaning of “at least one of a first item, a second item, and a thirditem” denotes the combination of all items proposed from two or more ofthe first item, the second item, and the third item as well as the firstitem, the second item, or the third item.

Features of various embodiments of the present invention may bepartially or overall coupled to or combined with each other, and may bevariously inter-operated with each other and driven technically as thoseskilled in the art can sufficiently understand. The embodiments of thepresent invention may be carried out independently from each other, ormay be carried out together in co-dependent relationship.

Hereinafter, exemplary embodiments of an organic light emitting displaydevice according to the present invention will be described in detailwith reference to the accompanying drawings. In the specification, inadding reference numerals for elements in each drawing, it should benoted that like reference numerals already used to denote like elementsin other drawings are used for elements wherever possible. In thefollowing description, when the detailed description of the relevantknown function or configuration is determined to unnecessarily obscurethe important point of the present invention, the detailed descriptionwill be omitted.

FIG. 1 is a cross-sectional view for describing an organic lightemitting display device according to an embodiment. FIG. 2 is a diagramfor describing a configuration of a touch sensing layer illustrated inFIG. 1. FIG. 3 is a cross-sectional view taken along line I-I′illustrated in FIG. 2.

Referring to FIGS. 1 to 3, the organic light emitting display deviceaccording to an embodiment may include (i) a display layer 110Aincluding a substrate 10, a pixel array layer 100, and an encapsulationlayer 300, (ii) a touch sensing layer 500, (iii) a cover window 700, and(iv) a touch driving circuit 900.

The substrate 10, a base substrate, may include a plastic material or aglass material. The substrate 10 according to an embodiment may beformed of a flexible plastic material, for example, opaque or coloredpolyimide (PI). The substrate 10 according to an embodiment may bemanufactured by curing polyimide resin which is coated on a top of arelease layer provided on a relatively thick carrier substrate to have acertain thickness. Here, the carrier substrate may be separated from thesubstrate 10 by releasing the release layer through a laser releaseprocess.

Additionally, the organic light emitting display device according to anembodiment may further include a back plate which is coupled to a bottomof the substrate 10 with respect to a vertical axis direction Z (or athickness direction of the substrate). The back plate may maintain thesubstrate 10 in a planar state. The back plate according to anembodiment may include a plastic material, for example,polyethyleneterephthalate (PET). The back plate may be laminated on thebottom of the substrate 10 separated from the carrier substrate, therebymaintaining the substrate 10 in a planar state.

The pixel array layer 100 may include a plurality of pixels SP that areprovided on the substrate 10 to display an image.

The plurality of pixels SP may be respectively provided in a pluralityof pixel areas defined by a plurality of gate lines, a plurality of datalines, and a plurality of pixel driving power lines. Each of theplurality of pixels SP may be an area corresponding to a minimum unitthat actually emits light, and may be defined as a subpixel. At leastthree adjacent pixels SP may configure one unit pixel for displayingcolors. For example, the one unit pixel may include a red pixel, a greenpixel, and a blue pixel which are adjacent to each other, and mayfurther include a white pixel so as to enhance luminance.

The plurality of pixels SP according to an embodiment may each include apixel circuit PC, a planarization layer PL, an anode electrode AE, abank layer BL, an organic light emitting device ED, and a cathodeelectrode CE.

The pixel circuit PC may be provided in a circuit area which is definedin a corresponding pixel SP, and may be connected to a gate line, a dataline, and a pixel driving power line which are adjacent thereto. Thepixel circuit PC may control a current flowing in the organic lightemitting device ED according to a data signal supplied through the dataline in response to a scan pulse supplied through the gate line, basedon a pixel driving power supplied through the pixel driving power line.The pixel circuit PC according to an embodiment may include a switchingthin film transistor (TFT), a driving TFT, and a capacitor.

The TFTs may each include a gate electrode, a gate insulation layer, asemiconductor layer, a source electrode, and a drain electrode. Here,each of the TFTs may be amorphous silicon (a-Si) TFT, a poly-Si TFT, anoxide TFT, an organic TFT, or the like.

The switching TFT may include a gate electrode connected to the gateline, a first electrode connected to the data line, and a secondelectrode connected to a gate electrode of the driving TFT. Here, eachof the first and second electrodes of the switching TFT may be a sourceelectrode or a drain electrode depending on a direction of a current.The switching TFT may be turned on according to the scan pulse suppliedthrough the gate line to supply the data signal supplied through thedata line to the driving TFT.

The driving TFT may be turned on by a voltage supplied through theswitching TFT and/or a voltage of the capacitor to control an amount ofcurrent which flows from the pixel driving power line to the organiclight emitting device ED. To this end, the driving TFT according to anembodiment may include a gate electrode connected to the secondelectrode of the switching TFT, a drain electrode connected to the pixeldriving power line, and a source electrode connected to the organiclight emitting device ED. The driving TFT may control a data currentflowing from the pixel driving power line to the organic light emittingdevice ED, based on the data signal supplied through the switch TFT, andthus, the organic light emitting device ED may emit light havingbrightness proportional to the data signal.

The capacitor may be provided in an overlapping area between the gateelectrode and the source electrode of the driving TFT. The capacitor maystore a voltage corresponding to the data signal supplied to the gateelectrode of the driving TFT and may turn on the driving TFT with thestored voltage.

In addition, the organic light emitting display device according to anembodiment may further include a scan driving circuit which is providedin a non-display area. The scan driving circuit may generate a scanpulse according to a gate control signal input thereto and may supplythe scan pulse to the gate line. The scan driving circuit according toan embodiment may be provided in an arbitrary non-display area, whereenables the scan pulse to be supplied to the gate line, of thenon-display area provided on the substrate 10 along with the TFTs of thepixel SP.

The planarization layer PL may be provided on the substrate 10 to coverthe pixel circuit PC and may provide a planarization surface on thesubstrate 10 where the TFTs are provided.

The anode electrode AE may be provided in a pattern type on theplanarization layer PL which overlaps an opening area defined in each ofthe pixel areas. The anode electrode AE may be connected to the sourceelectrode of the driving TFT, provided in the pixel circuit PC, througha contact hole provided in the planarization layer PL. The anodeelectrode AE may be formed of a metal material which is high inreflectivity, and for example, may include a material such as gold (Au),silver (Ag), aluminum (Al), molybdenum (Mo), magnesium (Mg), and/or thelike, or may include an alloy thereof. However, the present embodimentis not limited thereto.

The bank layer BL may be provided on the planarization layer PL to coveran edge of the anode electrode AE and the pixel circuit PC to define theopening area of each pixel area. The bank layer BL according to anembodiment may include an organic material such as benzocyclobutene(BCB), acryl, polyimide, and/or the like. In addition, the bank layer BLmay be formed of a photosensitive material containing a black pigment.In this case, the bank layer BL may act as a light blocking member (or ablack matrix).

The organic light emitting device ED may be provided on the anodeelectrode AE in the opening area defined by the bank layer BL. Theorganic light emitting device ED may be provided in a structure where ahole injection layer, a hole transport layer, an organic emission layer,an electron transport layer, and an electron injection layer aresequentially stacked. Here, one or more of the hole injection layer, thehole transport layer, the electron transport layer, and the electroninjection layer may be omitted. The organic emission layer according toan embodiment may be provided to emit lights of different colors (forexample, red, green, and blue) in each pixel. According to anotherembodiment, the organic emission layer may be formed to emit lights ofthe same color (for example, white) in each pixel, and in this case, theorganic light emitting device ED may include at least two organicemission layers.

The cathode electrode CE may be provided to cover the organic lightemitting device ED and the bank layer BL and may be connected to theorganic light emitting device ED in each pixel area in common. Thecathode electrode CE may be formed of a transparent metal material whichis high in light transmittance. The cathode electrode CE according to anembodiment may include a transparent conductive material (for example,indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide(IZTO), indium cesium oxide (ICO), indium tungsten oxide (IWO), etc.)such as transparent conductive oxide (TCO) and/or the like. Optionally,in the present embodiment, the cathode electrode CE may be formed of anamorphous transparent conductive material, for minimizing damage of theorganic light emitting device ED which is caused by a processtemperature when forming the cathode electrode CE.

The encapsulation layer 300 may be formed to cover the pixel array layer100, for protecting the organic light emitting device ED vulnerable toexternal water or oxygen by preventing the water from penetrating intoeach pixel SP. That is, the encapsulation layer 300 may be provided onthe substrate 10 to cover the cathode electrode CE. The encapsulationlayer 300 according to an embodiment may be formed of an inorganicmaterial layer or an organic material layer, or may be formed in amulti-layer structure where an inorganic material layer and an organicmaterial layer are alternately stacked.

The encapsulation layer 300 according to an embodiment may include afirst inorganic material layer 310 which is provided to cover thecathode electrode CE, an organic material layer 330 covering the firstinorganic material layer 310, and a second inorganic material layer 350covering the organic material layer 330.

The first inorganic material layer 310 may be disposed adjacent to theorganic light emitting device ED and may be formed of an inorganicinsulating material, which is capable of being deposited at a lowtemperature, such as nitride silicon (SiNx), oxide silicon (SiOx),oxynitride silicon (SiON), oxide aluminum (Al₂O₃), or the like. In thiscase, since the organic emission layer is vulnerable to a hightemperature, the first inorganic material layer 310 may be formed by alow temperature process in a low temperature atmosphere, for example,100 C.° or less. Accordingly, in the present embodiment, the organiclight emitting device ED is prevented from being damaged by a hightemperature atmosphere applied to a process chamber when forming thefirst inorganic material layer 310.

The organic material layer 330 may be provided on the substrate 10 tocover a whole top of the first inorganic material layer 310. The organicmaterial layer 330 may relax a stress between layers caused by bendingof the organic light emitting display device. The organic material layer330 according to an embodiment may include an organic material such asBCB, acryl, polyimide, silicon oxycarbon (SiOC), and/or the like.

The second inorganic material layer 350 may be provided on the substrate10 to cover a whole top of the organic material layer 330 and cover eachof side surfaces of the first inorganic material layer 310. The secondinorganic material layer 350 primarily prevents water or oxygen frompenetrating into the organic material layer 330 and the first inorganicmaterial layer 310 from the outside of the organic light emittingdisplay device. The second inorganic material layer 350 according to anembodiment may be formed of an inorganic insulating material, which iscapable of being deposited at a low temperature, such as SiNx, SiOx,SiON, Al₂O₃, or the like.

The substrate 10, the pixel array layer 100, and the encapsulation layer300 may configure an organic light emitting display panel.

The touch sensing layer 500 may sense a position and a touch force of auser touch on the cover window 700, and may be directly provided on theencapsulation layer 300 of the organic light emitting display panel.That is, the touch sensing layer 500 may not be separately manufacturedor may not be indirectly coupled to a top of the encapsulation layer 300by a separate optical adhesive, and may be directly formed on the top ofthe encapsulation layer 300 so as to reduce a thickness of the organiclight emitting display device.

The touch sensing layer 500 according to an embodiment may include afirst touch electrode layer 510 provided on the encapsulation layer 300,a second touch electrode layer 530 provided on the first touch electrodelayer 510, and a pressure reaction member 550 disposed between the firsttouch electrode layer 510 and the second touch electrode layer 530.

The first touch electrode layer 510 may include a plurality of firsttouch electrodes TE1 and a plurality of second touch electrodes TE2,which are directly coupled to the top of the encapsulation layer 300.

The plurality of first touch electrodes TE1 may be directly formed onthe top of the encapsulation layer 300 and may each act as a first touchdriving electrode for sensing a touch position based on a user touch.The plurality of first touch electrodes TE1 may be spaced apart fromeach other by a certain interval along a first horizontal axis directionX of the substrate 10 and may be directly formed on the top of theencapsulation layer 300 in parallel with a second horizontal axisdirection Y of the substrate 10.

Each of the plurality of first touch electrodes TE1 according to anembodiment may include a plurality of first touch electrode patterns TE1a, which are arranged at certain intervals along the second horizontalaxis direction Y of the substrate 10, and a plurality of connectionpatterns TE1 b which electrically connect the first touch electrodepatterns TE1 a adjacent to each other in the second horizontal axisdirection Y.

The plurality of first touch electrode patterns TE1 a and the pluralityof connection patterns TE1 b may be directly formed on the top of theencapsulation layer 300. Each of the plurality of first touch electrodepatterns TE1 a may have a rectangular shape, an octagonal shape, acircular shape, a lozenged shape, or the like, and each of the pluralityof connection patterns TE1 b may have a bar shape.

Each of the plurality of first touch electrodes TE1 may be connected tothe touch driving circuit 900 through a corresponding first routing lineamong a plurality of first routing lines RL1 provided on the substrate10. The plurality of first touch electrodes TE1 may receive a firsttouch driving pulse supplied from the touch driving circuit 900 during afirst touch sensing period (or a touch position sensing period). Duringa second touch sensing period (or a touch force sensing period), theplurality of first touch electrodes TE1 may be electrically floated bythe touch driving circuit 900. Here, the plurality of first routinglines RL1 may be connected to the touch driving circuit 900 through afirst flexible printed circuit film.

The plurality of second touch electrodes TE2 may be directly formed onthe top of the encapsulation layer 300 and may each act as a touchsensing electrode for sensing a touch based on a user touch. Theplurality of second touch electrodes TE2 may be directly formed on thetop of the encapsulation layer 300 in parallel with the first horizontalaxis direction X of the substrate 10 and may be arranged at certainintervals along the second horizontal axis direction Y of the substrate10.

Each of the plurality of second touch electrodes TE2 according to anembodiment may include a plurality of second touch electrode patternsTE2 a, which are arranged at certain intervals along the firsthorizontal axis direction X of the substrate 10, and a plurality ofbridge patterns TE2 b which electrically connect the second touchelectrode patterns TE2 a adjacent to each other in the first horizontalaxis direction X.

The plurality of second touch electrode patterns TE2 a may be directlyformed on the top of the encapsulation layer 300 corresponding to aportion between the first touch electrode patterns TE1 a adjacent toeach other in the second horizontal axis direction Y. Each of theplurality of second touch electrode patterns TE2 a may have a shapewhich is the same as that of the first touch electrode patterns TE1 a.

The plurality of bridge patterns TE2 b may be provided on a layerdifferent from the second touch electrode patterns TE2 a and mayelectrically connect two second touch electrode patterns TE2 a which areadjacent to each other and are separated from each other by theconnection pattern TE1 b of the first touch electrode TE1. In this case,each of the plurality of bridge patterns TE2 b and the connectionpattern TE1 b of the first touch electrode TE1 may be electricallydisconnected from each other by a touch insulation layer 511.

The touch insulation layer 511 may be provided on the encapsulationlayer 300 to cover the plurality of first touch electrodes TE1 and theplurality of second touch electrode patterns TE2 a and may have athickness of 500 Å to 5 μm. The touch insulation layer 511 may be formedof an organic material or an inorganic material. If the touch insulationlayer 511 is formed of the organic material, the touch insulation layer511 may be provided by a coating process of coating the organic materialon the encapsulation layer 300 and a curing process of curing the coatedorganic material at a temperature of 100 C.° or less. If the touchinsulation layer 511 is formed of the inorganic material, the touchinsulation layer 511 may be provided by the inorganic material depositedon the encapsulation layer 300 through a low temperature chemicaldeposition process and a cleaning process which are alternatelyperformed twice or more.

Both edges of each of the plurality of bridge patterns TE2 a may beconnected to the second touch electrode patterns TE2 a adjacent to theconnection pattern TE1 b of the first touch electrode TE1 through acontact hole CH provided in the touch insulation layer 511 to overlap anedge of the adjacent second touch electrode patterns TE2 a. Therefore, aplurality of second touch electrode patterns TE2 a which are spacedapart from each other with the connection pattern TE1 b of the firsttouch electrode TE1 therebetween may be electrically connected to eachother by a plurality of bridge patterns TE2 b to configure one secondtouch electrode TE2. The plurality of bridge patterns TE2 b according toan embodiment may be formed of a transparent conductive material (forexample, ITO, IZO, IZTO, ICO, IWO, etc.) such as TCO and/or the like, ormay be formed of a metal material, which is strong in corrosionresistance and acid resistance, such as Al, titanium (Ti), copper (Cu),Mo, and/or the like. The plurality of bridge patterns TE2 b may beprovided by a physical deposition process such as room temperaturesputtering or a chemical deposition process such as low temperaturechemical vapor deposition and a patterning process which includes aphotolithography process and an etching process.

Each of the plurality of second touch electrodes TE2 may be connected tothe touch driving circuit 900 through a corresponding second routingline among a plurality of second routing lines RL2 provided on thesubstrate 10. The plurality of second touch electrodes TE2 may be usedas a common touch sensing electrode for sensing a touch position and atouch force based on a user touch. Here, the plurality of second routinglines RL2 may be connected to the touch driving circuit 900 through thefirst flexible printed circuit film.

The plurality of first touch electrodes TE1 and the plurality of secondtouch electrodes TE2 according to the present embodiment may be formedof an amorphous transparent conductive material, for example, amorphousITO. For example, the plurality of first and second touch electrodes TE1and TE2 may be formed of an amorphous transparent conductive material bya low temperature deposition process having a process temperature of 100C.° or less, for preventing or minimizing damage of the pixel arraylayer 100 which is caused by a process temperature for forming the firstand second touch electrodes TE1 and TE2. That is, if the first andsecond touch electrodes TE1 and TE2 are formed of a crystallinetransparent conductive material, there is a problem where the pixelarray layer 100 is damaged by a high temperature thermal treatmentprocess performed for securing a low resistance value. In order to solvethe problem, in the present embodiment, the first touch electrodes TE1and the second touch electrodes TE2 may be formed of the amorphoustransparent conductive material through a low temperature metaldeposition process.

The pressure reaction member 550 may be provided on the encapsulationlayer 300 to cover the first touch electrode layer 510. That is, thepressure reaction member 550 may be directly provided on theencapsulation layer 300 where the first touch electrode layer 510 isprovided, and may cover the first touch electrode layer 510. Thepressure reaction member 550 according to an embodiment may haveelectrical characteristic which is changed based on a touch force (or atouch pressure) of a user, and thus, may act as a pressure reactionsensor for sensing the touch force of the user.

The pressure reaction member 550 according to an embodiment may includea piezoelectric material having a piezoelectric effect. Here, thepiezoelectric effect may denote a phenomenon in which a crystalstructure is deformed or twisted by a force applied thereto, thusrelative positions of a positive (+) ion and a negative ion (−) arechanged, and a potential difference occurs, for example, between thefirst touch electrode layer 510 and the second touch electrode layer 530due to dielectric polarization. In an embodiment in which the pressurereaction member 550 includes piezoelectric materials, the electricalcharacteristic of the pressure reaction member 550 is a capacitance ofthe pressure reaction member 550 between the first touch electrode layer510 and the second touch electrode layer 530 induced due to thepotential difference. By measuring a change in the capacitance of thepressure reaction member 550, an amount of force of a touch on the coverwindow 700 can be determined.

The piezoelectric material according to an embodiment may include one ofpolyvinylidene difluoride (PVDF), lead zirconate titanate (PZT), BaTiO₃,and parylene-C, but may include a material having the piezoelectriceffect without being limited thereto. For example, the PVDF is asemicrystalline ferroelectric polymer, having a high elastic coefficientand good flexibility. Here, the PVDF may have an elastic coefficientbetween 300 and 2000 MPa. The flexibility of PVDF may increase as theelastic coefficient is reduced.

The PVDF is easy to manufacture as a film, and is light and flexible. Inaddition PVDF can withstand a large impact. Therefore, the pressurereaction member 550 according to an embodiment may include the PVDF.

According to another embodiment, the pressure reaction member 550 mayinclude a piezoresistive material having a piezoresistive effect. Here,the piezoresistive effect may denote a phenomenon in which conductionenergy is generated by applied pressure or force, thus an electriccharge moves to a conduction band, and an electrical resistance (orresistivity) of a material varies. The piezoresistive effect causes avariation of an electrical resistance, and thus, is differentiated fromthe piezoelectric effect that causes a variation of an electricalpotential. In an embodiment in which the pressure reaction member 550includes piezoresistive materials, the electrical characteristic of thepressure reaction member 550 is a resistance of the pressure reactionmember 550 between the first touch electrode layer 510 and the secondtouch electrode layer 530. By measuring a change in the resistance, anamount of force of a touch on the cover window 700 can be determined.

A material having the piezoresistive effect may be metal, semiconductor,a conductive polymer, a conductive composite, or the like. Rubber haslower Young's modulus than other materials, and thus, if the rubber isused as a substrate of a composite, the composite can achieve highflexibility. Accordingly, the rubber may be sufficiently used as amaterial for sensing a touch force and may have elasticity which isrestored to the original shape without being largely deformed despiterepeated deformation. Also, silicone rubber in the conductive compositeis good in heat resistance, cold resistance, weather resistance, andwater resistance. If the silicone rubber includes a conductive filler,the silicone rubber can have the piezoresistive effect. Here, siliconerubber may have an elastic coefficient between 1 and 10 MPa.

The piezoresistive material according to an embodiment may include apolymer and a conductive filler. The polymer according to an embodimentmay include rubber or silicon rubber. The conductive filler according toan embodiment may include one of metal, semiconductor metal oxide, and acarbon-based material. For example, the metal may be nickel (Ni), copper(Cu), silver (Ag), aluminum (Al), iron (Fe), or the like. Thesemiconductor metal oxide may be vanadium oxide (V₂O₃), titanium oxide(TiO), or the like. The carbon-based material may be carbon black,graphite, graphene, carbon nano tube (CNT), or the like.

According to an experiment, as shown in FIG. 4, it can be seen that asapplied pressure increases, a resistance value of the piezoresistivematerial is progressively lowered.

The second touch electrode layer 530 may be directly provided on a topof the pressure reaction member 550. That is, the second touch electrodelayer 530 may include a plurality of third touch electrodes TE3 whichare directly provided on the top of the pressure reaction member 550 tointersect the plurality of second touch electrodes TE2.

The plurality of third touch electrodes TE3 may directly contact thepressure reaction member 550 and may each act as a second touch drivingelectrode for sensing a touch force based on a user touch. The pluralityof third touch electrodes TE3 may be directly formed on the top of thepressure reaction member 550 and may be arranged at certain intervalsalong the first horizontal axis direction X of the substrate 10 inparallel with the second horizontal axis direction Y of the substrate10. The plurality of third touch electrodes TE3 according to anembodiment may each be patterned in a bar shape, an octagonal shape, acircular shape, or a lozenged shape to respectively overlap theplurality of second touch electrodes TE2, but are not limited thereto.In other embodiments, the plurality of third touch electrodes TE3 mayeach be patterned in a shape which is the same as that of each of theplurality of second touch electrodes TE2. In this case, each of theplurality of third touch electrodes TE3 may include a plurality of thirdtouch electrode patterns overlapping the plurality of second touchelectrodes TE2 and a plurality of connection patterns which electricallyconnect the third touch electrode patterns adjacent to each other in thesecond horizontal axis direction Y.

Each of the plurality of third touch electrodes TE3 may be connected tothe touch driving circuit 900 through a corresponding third routing lineamong a plurality of third routing lines RL3 provided on the substrate10. The plurality of third touch electrodes TE3 may be electricallyfloated by the touch driving circuit 900 during the first touch sensingperiod. During the second touch sensing period, the plurality of thirdtouch electrodes TE3 may receive a second touch driving pulse suppliedfrom the touch driving circuit 900. Here, the plurality of third routinglines RL3 may be connected to the touch driving circuit 900 through asecond flexible printed circuit film.

Since the plurality of third touch electrodes TE3 according to thepresent embodiment is directly provided on the top of the pressurereaction member 550, the plurality of third touch electrodes TE3 may beformed of an amorphous transparent conductive material (for example,amorphous ITO), based on the same reason as that of the plurality offirst touch electrodes TE1 and the plurality of second touch electrodesTE2.

The second touch electrode layer 530 according to the present embodimentmay include a plurality of secondary electrodes SE1 and SE2 which areprovided along with the plurality of third touch electrodes TE3 and aredisposed adjacent to at least one of one side TE3 a and the other sideTE3 b of each of the plurality of third touch electrodes TE3. That is,the second touch electrode layer 530 according to an embodiment mayinclude a plurality of first secondary electrodes SE1, which areprovided adjacent to and in parallel with the one side TE3 a of each ofthe third touch electrodes TE3, and a plurality of second secondaryelectrodes SE2 which are provided adjacent to and in parallel with theother side TE3 b of each of the third touch electrodes TE3. Each of theplurality of first and second secondary electrodes SE1 and SE2 may havea shape which is the same as that of each of the third touch electrodesTE3.

Each of the plurality of first secondary electrodes SE1 may be connectedto the touch driving circuit 900 through a corresponding first secondaryrouting line among a plurality of first secondary routing lines SRL1,and each of the plurality of second secondary electrodes SE2 may beconnected to the touch driving circuit 900 through a correspondingsecond secondary routing line among a plurality of second secondaryrouting lines SRL2. Each of the plurality of first and second secondaryelectrodes SE1 and SE2 may be floated by the touch driving circuit 900or may be electrically connected to the third routing line RL3 adjacentthereto. In more detail, the plurality of first secondary electrodes SE1and the plurality of second secondary electrodes SE2 may be electricallyfloated during the first touch sensing period. On the other hand, duringthe second touch sensing period, the plurality of first secondaryelectrodes SE1 and the plurality of second secondary electrodes SE2 maybe electrically connected to the third touch electrode TE3 adjacentthereto and may receive the second touch driving pulse supplied from thetouch driving circuit 900, and thus, an overlapping area between thesecond touch electrodes TE2 and the third touch electrodes TE3increases, thereby enhancing an efficiency of touch force sensing. Here,the plurality of first secondary routing lines SRL1 and the plurality ofsecond secondary routing lines SRL2 may be connected to the touchdriving circuit 900 through the second flexible printed circuit film.

The plurality of first secondary electrodes SE1 and the plurality ofsecond secondary electrodes SE2 may be used as a touch force sensingelectrode for sensing a touch force and may be used as a floatingelectrode which enables a touch position to be sensed.

In addition, in FIG. 2, each of the plurality of first secondaryelectrodes SE1 and the plurality of second secondary electrodes SE2 isillustrated as having a bar shape, but is not limited thereto. In otherembodiments, in order to increase a transmittance of light emitted fromeach pixel SP, each of the plurality of first secondary electrodes SE1and the plurality of second secondary electrodes SE2 may be formed in aplurality of line structures, mesh structures, or trapezoid structureswhich are electrically connected to each other, or may include aplurality of openings which are arranged at certain intervals in a slitor lattice type.

The pressure reaction member 550 may be disposed between the first touchelectrode layer 510 and the second touch electrode layer 530 and on theplurality of first touch electrodes TE1 and the plurality of secondtouch electrodes TE2. Accordingly, a touch sensor TS may be providedbetween adjacent first and second touch electrodes TE1 and TE2, and aforce sensor FS may be provided between adjacent second and third touchelectrodes TE2 and TE3.

The touch sensor TS according to an embodiment may be defined as amutual capacitance which is provided in the pressure reaction member 550between adjacent first and second touch electrodes TE1 and TE2.

The force sensor FS according to an embodiment may be a piezoelectricsensor or a piezoresistive sensor between adjacent second and thirdtouch electrodes TE2 and TE3. Here, for example, if the pressurereaction member 550 includes the piezoelectric material, the forcesensor FS may act as the piezoelectric sensor. As another example, ifthe pressure reaction member 550 includes the piezoresistive material,the force sensor FS may act as the piezoresistive sensor.

An electric charge may be charged into the mutual capacitance of thetouch sensor TS according to the first touch driving pulse applied tothe first touch electrode TE1, and the charged electric charge may varyaccording to whether a user touch is made. Therefore, a touch positionmay be sensed by using a touch position calculation algorithm whichmodels a reduction in the mutual capacitance provided in the touchsensor TS, based on a user touch.

A voltage of the force sensor FS according to an embodiment may varyaccording to the piezoelectric effect based on an elasticity change ofthe pressure reaction member 550 caused by a touch force of a user. Inthis case, as pressure based on the touch force of the user becomeshigher, the voltage of the force sensor FS may increase, and thus, atouch force level may be sensed by using a touch force level calculationalgorithm which models a voltage increase rate of the force sensor FS,based on the touch force of the user.

According to another embodiment, a resistance of the force sensor FS mayvary according to the piezoresistive effect based on an elasticitychange of the pressure reaction member 550 caused by a touch force of auser. In this case, as pressure based on the touch force of the userbecomes higher, the resistance of the force sensor FS may be reduced,and thus, a touch force level may be sensed by using a touch force levelcalculation algorithm which models a voltage variation rate with respectto a resistance reduction rate of the force sensor FS, based on thetouch force of the user. That is, in the present embodiment, aresistance variation of the force sensor FS may be calculated by sensinga voltage variation of the force sensor FS caused by the touch force ofthe user, and a touch force level corresponding to the varied resistancevalue may be calculated by using a lookup table.

Referring again to FIGS. 1 to 3, the cover window 700 may be coupled toa top of the touch sensing layer 500. That is, the cover window 700 maybe coupled to the top of the pressure reaction member 550, where theplurality of third touch electrodes TE3 are provided, through an opticaladhesive member 600. Here, the optical adhesive member 600 may includean optical clear adhesive (OCA), an optical clear resin (OCR), or thelike. The cover window 700 may cover the touch sensing layer 500 toprotect the pixel array layer 100 as well as the touch sensing layer 500and may act as a touch surface for a user touch.

The cover window 700 according to an embodiment may be formed oftempered glass, transparent plastic, a transparent film, or the like.For example, the cover window 700 may include at least one of sapphireglass and gorilla glass. As another example, the cover window 700 mayinclude at least one of polyethyleneterephthalate (PET), polycarbonate(PC), polyethersulfone (PES), polyethylenapthanate (PEN), polyimide(PI), and polynorborneen (PNB). The cover window 700 may includetempered glass, based on scratch and transparency.

The touch driving circuit 900 may be connected to the plurality of firsttouch electrodes TE1, the plurality of second touch electrodes TE2, andthe plurality of third touch electrodes TE3. That is, the touch drivingcircuit 900 may be connected to the plurality of first touch electrodesTE1, the plurality of second touch electrodes TE2, and the plurality ofthird touch electrodes TE3 through the plurality of first to thirdrouting lines RL1, RL2 and RL3 provided on the substrate 10 in aone-to-one relationship and may be connected to the plurality of firstand second secondary electrodes SE1 and SE2 through the plurality offirst and second secondary routing lines SRL1 and SRL2 provided on thesubstrate 10 in a one-to-one relationship.

The touch driving circuit 900 according to an embodiment maytime-divisionally drive the touch sensing layer 500 in the first touchsensing period and the second touch sensing period in response to atouch mode signal supplied from a host control circuit, and in each ofthe first touch sensing period and the second touch sensing period, whena touch event occurs, the touch driving circuit 900 may drive the touchsensing layer 500 in a haptic mode. Here, the first touch sensing periodmay be defined as a touch position sensing period for sensing a touchevent and a touch position by a user, the second touch sensing periodmay be defined as a touch force sensing period for sensing a touchforce, and the haptic mode may be defined as a haptic feedback periodwhere a haptic effect is provided in response to a touch event. In thiscase, in the second touch sensing period, a touch force may be sensed ina touch event area of the first touch sensing period, for shortening atouch force sensing time. That is, the touch driving circuit 900 mayprimarily perform touch position sensing through global touch sensing orgroup touch sensing to detect a touch event area, and may secondarilyperform touch force sensing on only the touch event area through localforce touch sensing.

During the first touch sensing period, as illustrated in FIG. 5A, thetouch driving circuit 900 may electrically float the plurality of thirdtouch electrodes TE3 and the plurality of first and second secondaryelectrodes SE1 and SE2, apply a first touch driving pulse TDP1 to atleast one of the plurality of first touch electrodes TE1, and sense amutual capacitance variation of the touch sensor TS, caused by a usertouch, through the plurality of second touch electrodes TE2 to generatea first touch sensing signal. For example, during the first touchsensing period, the touch driving circuit 900 may sequentially apply thefirst touch driving pulse TDP1 to the plurality of first touchelectrodes TE1 and may sense the mutual capacitance variation of thetouch sensor TS, provided between the first touch electrode TE1 to whichthe first touch driving pulse TDP1 is applied and the second touchelectrode TE2 adjacent thereto, through the plurality of second touchelectrodes TE2 to generate the first touch sensing signal.

During the second touch sensing period, the touch driving circuit 900may electrically float the plurality of first touch electrodes TE1,apply a second touch driving pulse TDP2 to at least one of the pluralityof third touch electrodes TE3, and sense a voltage variation of theforce sensor FS, caused by a touch force of a user, through theplurality of second touch electrodes TE2 to generate a second touchsensing signal. For example, during the second touch sensing period, thetouch driving circuit 900 may sequentially apply the second touchdriving pulse TDP2 to the plurality of third touch electrodes TE3 andmay sense a voltage variation (or a resistance variation) of the forcesensor FS, provided between the third touch electrode TE3 to which thesecond touch driving pulse TDP2 is applied and the second touchelectrode TE2 overlapping the third touch electrode TE3, through theplurality of second touch electrodes TE2 to generate the second touchsensing signal.

In addition, the touch driving circuit 900 may determine the presence ofa touch event to calculate a touch event area, based on the first touchsensing signal generated through sensing during the first touch sensingperiod, apply the second touch driving pulse TDP2 to at least one thirdtouch electrode TE3 provided in the touch event area during the secondtouch sensing period, and sense a voltage variation of the force sensorFS of the pressure reaction member 550, caused by a touch force of auser, through the plurality of second touch electrodes TE2 to generatethe second touch sensing signal. Subsequently, based on the second touchsensing signal, the touch driving circuit 900 may calculate touchposition coordinates to output the touch position coordinates to thehost control circuit, or may calculate a touch force level and touchposition coordinates to output the touch force level and the touchposition coordinates to the host control circuit. That is, in thepresent embodiment, during the second touch sensing period, touch forcesensing may be locally performed on a touch event area which iscalculated through sensing in the first touch sensing period, therebyshortening a touch force sensing time for which a touch force of a useris sensed.

According to another embodiment, as illustrated in FIG. 5B, during thesecond touch sensing period, the touch driving circuit 900 mayelectrically float the plurality of first touch electrodes TE1,electrically connect each of the plurality of first and second secondaryelectrodes SE1 and SE2 to the third touch electrode TE3 adjacentthereto, apply the second touch driving pulse TDP2 to at least one ofthe plurality of third touch electrodes TE3, and sense a voltagevariation (or a resistance variation) of the force sensor FS of thepressure reaction member 550, caused by a touch force of a user, throughthe plurality of second touch electrodes TE2 to generate the secondtouch sensing signal. In this case, each of the plurality of third touchelectrodes TE3 respectively overlapping the plurality of second touchelectrodes TE2 may be electrically connected to the first and secondsecondary electrodes SE1 and SE2 adjacent thereto, and thus, anoverlapping area between the third touch electrode TE3 and the secondtouch electrode TE2 increases by an area of the first and secondsecondary electrodes SE1 and SE2. Therefore, the voltage (or theresistance) generated in the force sensor FS may further vary by an areaof the first and second secondary electrodes SE1 and SE2 connected tothe third touch electrode TE3, and thus, in present embodiment, thevoltage variation (or the resistance variation) of the force sensor FScaused by the touch force of the user is more easily sensed.

In addition, since the pressure reaction member 550 is disposed betweenthe first touch electrode layer 510 and the second touch electrode layer530, the pressure reaction member 550 may act as a haptic output device.That is, the organic light emitting display device according to thepresent embodiment may realize the haptic mode by using the pressurereaction member 550. The haptic mode according to an embodiment mayinclude a vibration haptic mode based on a vibration of the pressurereaction member 550 and an electrostatic haptic mode based on anelectrostatic force of the pressure reaction member 550.

In the vibration haptic mode according to an embodiment, the touchdriving circuit 900 may supply a first haptic driving signal to theplurality of first touch electrodes TE1 and may supply a second hapticdriving signal to the plurality of third touch electrodes TE3. Here, thefirst haptic driving signal may be a first alternating current (AC)signal having a constant frequency, and the second haptic driving signalmay be a direct current (DC) voltage having a constant voltage level. Inthe vibration haptic mode, the pressure reaction member 550 may berepeatedly expanded and contracted by a piezoelectric effect based onthe first AC signal applied to the plurality of first touch electrodesTE1 and the DC voltage applied to the plurality of third touchelectrodes TE3 to cause vibration, thereby providing a vibration hapticeffect. An intensity of the vibration may vary according to a frequencyand/or amplitude of the first AC signal. In this case, since thepressure reaction member 550 may act as an actuator that vibratesaccording to a haptic driving signal applied to each of the first touchelectrodes TE1 and the third touch electrodes TE3.

In the electrostatic haptic mode according to an embodiment, the touchdriving circuit 900 may supply the first haptic driving signal to theplurality of first touch electrodes TE1 and may supply a third hapticdriving signal to the plurality of third touch electrodes TE3. Here, thefirst haptic driving signal may be the first AC signal having a constantfrequency, and the third haptic driving signal may be a second AC signalhaving a frequency which is the same as or different from that of thefirst AC signal. In the electrostatic haptic mode, since the pressurereaction member 550 functions as an insulating layer, an electrostaticforce occurs between the electrodes and a user's finger in accordancewith the first AC signal and the second AC signal. Thus, the pressurereaction member 550 may provide an electrostatic haptic effect by theelectrostatic force. An intensity of the electrostatic force may varyaccording to a frequency and/or amplitude of each of the first andsecond AC signals.

The vibration haptic effect based on the vibration haptic mode may be amechanical vibration, and even when a relatively short touch occurs, thevibration haptic effect enables a user to recognize the relatively shorttouch. However, in the electrostatic haptic effect based on theelectrostatic haptic mode, when the relatively short touch occurs, it isdifficult for the user to recognize the relatively short touch.Therefore, the haptic mode may be set as the vibration haptic mode andthe electrostatic haptic mode, based on a touch duration. If the touchduration is equal to or more than a reference value, the haptic modeaccording to an embodiment may be set as the electrostatic haptic mode,and if the touch duration is less than the reference value, the hapticmode may be set as the vibration haptic mode. For example, if a usertouch is a temporary touch event corresponding to a click or a doubleclick, the haptic mode may be set as the vibration haptic mode. Also, ifthe user touch is a continuous touch event corresponding to a touch anddrag, the haptic mode may be set as the electrostatic haptic mode.

In addition, the touch driving circuit 900 may determine the presence ofa touch event, based on the first touch sensing signal generated throughsensing during the first touch sensing period and may perform the hapticmode corresponding to the touch event. For example, the touch drivingcircuit 900 may apply the haptic driving signal to the first and thirdtouch electrodes TE1 and TE3 provided in a user touch area according toa touch event sensed during the first touch sensing period, therebyproviding the user with a vibration feedback based on the vibrationhaptic effect or a tactile feedback based on the electrostatic hapticeffect in the user touch area.

As described above, since the touch sensing layer 500 is directlyprovided in the organic light emitting display panel, the organic lightemitting display device according to an embodiment has a thin thicknessdespite including the touch panel. The organic light emitting displaydevice may sense a mutual capacitance variation caused by a user touchto sense a touch position by the user, and may sense a voltage orresistance variation of the pressure reaction member 550 caused by atouch force of the user to sense the touch force of the user. Also, inthe organic light emitting display device according to an embodiment,the first and second secondary electrodes SE1 and SE2 may be connectedto the third touch electrode TE3 when sensing the touch force of theuser, and thus, an area of the third touch electrode TE3 overlapping thesecond touch electrode TE2 increases, thereby increasing an efficiencyof touch force sensing.

FIG. 6 is a diagram illustrating a modification example of a touchsensing layer in an organic light emitting display device according toan embodiment and is configured by electrically connecting the first andsecond secondary electrodes illustrated in FIG. 2. Therefore, only firstand second secondary electrodes and elements relevant thereto will bedescribed.

One side of each of the first and second secondary electrodes SE1 andSE2 may be electrically connected to each other by a connectionsecondary electrode SE3.

The connection secondary electrode SE3 may be spaced apart from one end(for example, one short side TE3 c) of the third touch electrode TE3 andmay be provided in parallel with the one short side TE3 c, and moreover,the connection secondary electrode SE3 may electrically connect one endsof the first and second secondary electrodes SE1 and SE2 which areparallel to each other with an adjacent third touch electrode TE3therebetween. Therefore, the connection secondary electrode SE3 mayconnect one ends of the first and second secondary electrodes SE1 andSE2 which are adjacent to one side TE3 a and the other side TE3 b of thethird touch electrode TE3. That is, each of the plurality of firstsecond electrodes SE1 may be provided adjacent to one side of acorresponding third touch electrode TE3. The connection secondaryelectrode SE3 may be provided in plurality. Each of the plurality ofconnection secondary electrodes SE3 may be spaced apart from the oneshort side TE3 c of the third touch electrode TE3 adjacent thereto, maybe parallel to the one short side TE3 c, and may extend from one end ofa corresponding first secondary electrode SE1. Also, each of theplurality of second secondary electrodes SE2 may be adjacent to theother side of a corresponding third touch electrode TE3 and may extendfrom an end of a corresponding connection secondary electrode SE3.Therefore, a plurality of secondary electrodes which include theplurality of first secondary electrodes SE1, the plurality of connectionsecondary electrodes SE3, and the plurality of second secondaryelectrodes SE2 may be electrically connected to each other, may beprovided on the same layer, and may have a ⊂-shape or a ⊃-shape, therebysurrounding sides of the third touch electrode TE3 other than the othershort side of the third touch electrode TE3. Here, the other short sideof the third touch electrode TE3 may be defined as a portion connectedto the secondary routing line SRL.

Since the one ends of the first and second secondary electrodes SE1 andSE2 are connected to each other by the connection secondary electrodeSE3, ones of the plurality of first and second secondary routing linesSRL1 and SRL2 may be omitted. In this case, according to the presentembodiment, a width of an edge of the substrate 10 where a routing lineis provided is reduced, and thus, a bezel width of the organic lightemitting display device is reduced.

FIG. 7 is a cross-sectional view for describing an organic lightemitting display device according to another embodiment and isconfigured by adding a function layer to the organic light emittingdisplay device illustrated in FIGS. 1 to 5B. Therefore, only a functionlayer and elements relevant thereto will be described.

Referring to FIG. 7, in the organic light emitting display deviceaccording to the present embodiment, the display layer 110B additionallyincludes a function layer 520 on the encapsulation layer 300. Thefunction layer 520 may be disposed between an encapsulation layer 300and a first touch electrode layer 510. The function layer 520additionally prevents an organic light emitting device ED from beingdamaged by external water or oxygen. Also, the function layer 520enhances the luminance characteristic of light emitted from each of aplurality of pixels SP.

The function layer 520 according to one or more embodiments may includea barrier film 522 disposed between the encapsulation layer 300 and thefirst touch electrode layer 510.

The barrier film 522 according to an embodiment may be adhered to awhole top of the encapsulation layer 300 by a first transparent adhesive521 to cover the whole top of the encapsulation layer 300. In this case,with respect to a vertical axis direction Z (or a thickness direction ofthe barrier film 522), a bottom of the barrier film 522 may be coupledto the encapsulation layer 300 by the first transparent adhesive 521,and a top of the barrier film 522 may be directly coupled to a bottom ofthe first touch electrode layer 510.

According to one or more embodiments, the function layer 520 may includethe barrier film 522, disposed between the encapsulation layer 300 andthe first touch electrode layer 510, and a light control film 524disposed between the barrier film 522 and the first touch electrodelayer 510.

The barrier film 522 may be disposed between the encapsulation layer 300and the light control film 524. That is, the barrier film 522 may beadhered to the whole top of the encapsulation layer 300 by the firsttransparent adhesive 521 to cover the encapsulation layer 300. In thiscase, the bottom of the barrier film 522 may be adhered to theencapsulation layer 300 by the first transparent adhesive 521, and thetop of the barrier film 522 may be directly coupled to a bottom of thelight control film 524 by a second transparent adhesive 523.

The light control film 524 may be adhered to the top of the barrier film522 by the second transparent adhesive 523 to cover the whole top of thebarrier film 522. In this case, the bottom of the light control film 524may be adhered to the top of the barrier film 522 by the secondtransparent adhesive 523, and a top of the light control film 524 may bedirectly coupled to the bottom of the first touch electrode layer 510.Also, the light control film 524 enhances the luminance characteristicof the light emitted from each pixel SP. For example, the light controlfilm 524 may be a polarizing film that polarizes the light emitted fromeach pixel SP, but may be an optical film for enhancing the luminancecharacteristic of the light emitted from each pixel SP without beinglimited thereto.

In the function layer 520 according to various embodiments, the barrierfilm 522 may be formed by coating an inorganic insulating material on anorganic insulation film. The barrier film 522 is for primarilypreventing water or oxygen from penetrating into each pixel SP and maybe formed of a material which is low in water vapor transmission rate.In addition, the barrier film 522 may act as a supporter that supportsthe bottom of the first touch electrode layer 510 in order for a touchforce of a user to be applied to the pressure reaction member 550. Also,the barrier film 522 may relax an impact which is applied to the organiclight emitting display device due to the touch force of the user,thereby preventing damage of the organic light emitting device ED.

Furthermore, in the organic light emitting display device according tothe present embodiment, a second touch electrode layer 530 may have astructure which is the same as that of the second touch electrode layerillustrated in FIG. 6.

Since the organic light emitting display device according to the presentembodiment includes the barrier film 522, the organic light emittingdisplay device according to the present embodiment has the same effectsas those of the organic light emitting display device illustrated inFIGS. 1 to 7, and moreover, the organic light emitting device ED is morestably prevented from being damaged by an impact and water or oxygen.

FIG. 8 is a cross-sectional view for describing an organic lightemitting display device according to another embodiment and isconfigured by changing a position of the function layer in the organiclight emitting display device illustrated in FIG. 7. Therefore, only afunction layer and elements relevant thereto will be described.

Referring to FIG. 8, in the organic light emitting display deviceaccording to the present embodiment, except that a function layer 520 isnot included in the display layer 110C but instead is disposed between atouch sensing layer 500 and a cover window 700 so as to additionallyprevent the touch sensing layer 500 from being damaged by external wateror oxygen, the function layer 520 according to the present embodimentmay have the same configuration as that of the function layer 520illustrated in FIG. 7. Therefore, only a configuration and anarrangement structure of the function layer 520 will be described.

The function layer 520 according to one or more embodiments may includea barrier film 522 disposed between the touch sensing layer 500 and thecover window 700.

The barrier film 522 according to an embodiment may be adhered to awhole top of the touch sensing layer 500 by a first transparent adhesive521 to cover the whole top of the touch sensing layer 500. In this case,a bottom of the barrier film 522 may be coupled to a second touchelectrode layer 530 of the touch sensing layer 500 by the firsttransparent adhesive 521, and a top of the barrier film 522 may bedirectly coupled to the cover window 700, namely, an optical adhesivemember 600.

According to one or more embodiments, the function layer 520 may includethe barrier film 522, disposed between the touch sensing layer 500 andthe cover window 700, and a light control film 524 disposed between thebarrier film 522 and the cover window 700.

The barrier film 522 may be disposed between the touch sensing layer 500and the light control film 524. That is, the barrier film 522 may beadhered to the whole top of the touch sensing layer 500 by the firsttransparent adhesive 521 to cover a whole top of the touch sensing layer500. In this case, the bottom of the barrier film 522 may be coupled tothe second touch electrode layer 530 of the touch sensing layer 500 bythe first transparent adhesive 521, and the top of the barrier film 522may be directly coupled to a bottom of the light control film 524 by asecond transparent adhesive 523.

The light control film 524 may be adhered to the top of the barrier film522 by the second transparent adhesive 523 to cover the whole top of thebarrier film 522. In this case, the bottom of the light control film 524may be adhered to the top of the barrier film 522 by the secondtransparent adhesive 523, and a top of the light control film 524 may bedirectly coupled to the bottom of the cover window 700, namely, theoptical adhesive member 600. Also, the light control film 524 enhancesthe luminance characteristic of light emitted from each pixel SP. Forexample, the light control film 524 may be a polarizing film thatpolarizes the light emitted from each pixel SP.

In the function layer 520 according to various embodiments, the barrierfilm 522 may be formed by coating an inorganic insulating material on anorganic insulation film. The barrier film 522 is for primarilypreventing water or oxygen from penetrating into each pixel SP and maybe formed of a material which is low in water vapor transmission rate.Also, the barrier film 522 may relax an impact which is applied to theorganic light emitting display device due to the touch force of theuser, thereby preventing an organic light emitting device ED from beingdamaged by the impact and additionally preventing the touch sensinglayer 500 from being damaged by water or oxygen.

Furthermore, in the organic light emitting display device according tothe present embodiment, the second touch electrode layer 530 may have astructure which is the same as that of the second touch electrode layerillustrated in FIG. 6.

Since the organic light emitting display device according to the presentembodiment includes the barrier film 522, the organic light emittingdisplay device according to the present embodiment has the same effectsas those of the organic light emitting display device illustrated inFIGS. 1 to 6, and moreover, the first touch electrode layer 510 isadditionally prevented from being damaged by water or oxygen.

FIG. 9 is a cross-sectional view for describing an organic lightemitting display device according to another embodiment, and FIG. 10 isa diagram for describing a touch sensing layer illustrated in FIG. 9.The drawings illustrate the organic light emitting display deviceconfigured by changing positions of the first and second touch electrodelayers in the touch sensing layer illustrated in FIG. 1. Similarly tothe display layer 110A in the embodiment shown in FIG. 2, the displaylayer 110D in this embodiment shown in FIG. 9 includes the substrate 10,the pixel array layer 100, and the encapsulation layer 300. Therefore,only a touch sensing layer will be described.

Referring to FIGS. 9 and 10, a touch sensing layer 500 of the organiclight emitting display device according to the present embodiment mayinclude a first touch electrode layer 530 provided on an encapsulationlayer 300, a second touch electrode layer 510 provided on the firsttouch electrode layer 530, and a pressure reaction member 550 disposedbetween the first touch electrode layer 530 and the second touchelectrode layer 510.

The second touch electrode layer 510 may include a plurality of firsttouch electrodes TE1 and a plurality of second touch electrodes TE2,which are directly coupled to a top of the pressure reaction member 550.The second touch electrode layer 510 corresponds to the first touchelectrode layer illustrated in FIGS. 1 to 3. Except that the pluralityof first touch electrodes TE1 and the plurality of second touchelectrodes TE2 are directly provided on the top of the pressure reactionmember 550, the second touch electrode layer 510 according to thepresent embodiment has the same configuration as that of the first touchelectrode layer illustrated in FIGS. 1 to 3, and thus, its detaileddescription is not provided.

The first touch electrode layer 530 according to an embodiment mayinclude one touch electrode TE3 which is directly coupled to a top ofthe encapsulation layer 300 and is provided to overlap the plurality ofsecond touch electrodes TE2 and the plurality of first touch electrodesTE1. The first touch electrode layer 530 corresponds to the second touchelectrode layer illustrated in FIGS. 1 to 3. Except that the first touchelectrode layer 530 includes the one touch electrode TE3 and is directlyprovided on a top of the encapsulation layer 300, the first touchelectrode layer 530 according to the present embodiment has the sameconfiguration as that of the second touch electrode layer illustrated inFIGS. 1 to 3, and thus, its detailed description is not provided.

In one embodiment, since the first touch electrode layer 530 includes asingle third touch electrode TE3 rather than a plurality of third touchelectrodes TE3, a single touch force may be sensed. That is, in anembodiment in which the organic light emitting display device includesthe plurality of third touch electrodes TE3, a touch force and a touchposition may be simultaneously sensed for each of two or more differenttouch areas. In an embodiment in which a single third touch electrodeTE3 is included in the first touch electrode layer 530, a multi-touchposition may be sensed through the first and second touch electrodes TE1and TE2 of the second touch electrode layer 510, and a single touchforce may be sensed through the single third touch electrode TE3 and thesecond touch electrodes TE2, hence a touch force sensing time can bereduced.

In addition, the first touch electrode layer 530 according to thepresent embodiment may include at least one third touch electrode TE3 asin the organic light emitting display device illustrated in FIGS. 1 to9, for sensing a multi-touch force. Furthermore, the first touchelectrode layer 530 may further include the above-described connectionsecondary electrode for enlarging an overlapping area between each ofthe plurality of third touch electrodes TE3 and the second touchelectrode TE2 in sensing a touch force.

The organic light emitting display device according to the presentembodiment may further include the function layer 520 illustrated inFIG. 7 or 8.

In the organic light emitting display device according to the presentembodiment, the first touch electrode layer 510 may be disposed closerto a touch surface than the second touch electrode layer 530, and thus,a sensitivity of touch position sensing is enhanced.

FIG. 11 is a cross-sectional view for describing an organic lightemitting display device according to an embodiment. FIG. 12 is a diagramfor describing a configuration of a touch sensing layer illustrated inFIG. 12. FIG. 13 is a cross-sectional view taken along line II-II′illustrated in FIG. 12. The organic light emitting display deviceaccording to the present embodiment is configured by changing the firsttouch electrode layer illustrated in FIG. 1. Similarly to the displaylayer 110A in the embodiment shown in FIG. 2, the display layer 110E inthis embodiment shown in FIG. 11 includes the substrate 10, the pixelarray layer 100, and the encapsulation layer 300. Therefore, only afirst touch electrode layer and elements relevant thereto will bedescribed.

Referring to FIGS. 11 to 13, in the organic light emitting displaydevice according to the present embodiment, a first touch electrodelayer 510 may include a plurality of first touch electrodes TE1 directlycoupled to a top of an encapsulation layer 300, an electrode insulationlayer 515 provided on the encapsulation layer 300 to cover the pluralityof first touch electrodes TE1, and a plurality of second touchelectrodes TE2 which are directly coupled to a top of the electrodeinsulation layer 515 and intersect the plurality of first touchelectrodes TE1.

The plurality of first touch electrodes TE1 may be directly formed onthe top of the encapsulation layer 300 and may each act as a first touchdriving electrode for sensing a touch position based on a user touch.The plurality of first touch electrodes TE1 may be spaced apart fromeach other by a certain interval along a second horizontal axisdirection Y of the substrate 10 and may be directly formed on the top ofthe encapsulation layer 300 in parallel with a first horizontal axisdirection X of the substrate 10. Each of the plurality of first touchelectrodes TE1 according to an embodiment may be provided in a bar shapewhich extends along the first horizontal axis direction X.

Each of the plurality of first touch electrodes TE1 may be connected toa touch driving circuit 900 through a corresponding first routing lineamong a plurality of first routing lines RL1 provided on the substrate10. The plurality of first touch electrodes TE1 may receive a firsttouch driving pulse supplied from the touch driving circuit 900 during afirst touch sensing period. During a second touch sensing period, theplurality of first touch electrodes TE1 may be electrically floated bythe touch driving circuit 900.

The electrode insulation layer 515 may be provided on the encapsulationlayer 300 to cover the plurality of first touch electrodes TE1.

The plurality of second touch electrodes TE2 may be directly formed on atop of the electrode insulation layer 515 and may each act as a touchsensing electrode for sensing a touch based on a user touch. Theplurality of second touch electrodes TE2 may be directly provided on thetop of the electrode insulation layer 515 and may be arranged at certainintervals along the first horizontal axis direction X of the substrate10 in parallel with the second horizontal axis direction Y of thesubstrate 10. That is, each of the plurality of second touch electrodesTE2 may be provided in a bar shape which extends along the secondhorizontal axis direction Y of the substrate 10 to intersect each of theplurality of first touch electrodes TE1.

The plurality of first touch electrodes TE1 and the plurality of secondtouch electrodes TE2 may intersect each other with the electrodeinsulation layer 515 therebetween, and thus, a touch sensor TS includinga mutual capacitance may be provided in the electrode insulation layer515 and at each of intersection portions of the plurality of first touchelectrodes TE1 and the plurality of second touch electrodes TE2. Anelectric charge may be charged into the mutual capacitance of touchsensor TS according to the first touch driving pulse applied to thefirst touch electrode TE1, and the charged electric charge may varyaccording to whether a user touch is made. Therefore, a touch positionmay be sensed by using a touch position calculation algorithm whichmodels a reduction in mutual capacitance included in the touch sensorTS, based on a user touch.

Optionally, the plurality of first touch electrodes TE1 and theplurality of third touch electrodes TE3 may be exchanged in theirdisposed positions. That is, similarly to FIG. 10, the plurality ofthird touch electrodes TE3 may be directly provided on the top of theencapsulation layer 300, and the plurality of first touch electrodes TE1may be directly provided on the top of the pressure reaction member 550.

The pressure reaction member 550 may be disposed between the first touchelectrode layer 510 and the second touch electrode layer 530 and may beformed of a material which is the same as that of the pressure reactionmember illustrated in FIG. 2.

The pressure reaction member 550 may be disposed between the pluralityof second touch electrodes TE2 and the plurality of third touchelectrodes TE3, thereby providing a force sensor FS between the secondtouch electrodes TE2 and the third touch electrodes TE3.

The force sensor FS according to an embodiment may have a voltage basedon a piezoelectric effect based on an elasticity change of the pressurereaction member 550 caused by a touch force of a user. In this case, aspressure based on the touch force of the user becomes higher, thevoltage of the force sensor FS may increase, and thus, a touch forcelevel may be sensed by using a touch force level calculation algorithmwhich models a voltage increase rate of the force sensor FS, based onthe touch force of the user.

According to another embodiment, the force sensor FS may a resistancevalue based on a piezoresistive effect based on an elasticity change ofthe pressure reaction member 550 caused by a touch force of a user. Inthis case, as pressure based on the touch force of the user becomeshigher, the resistance of the force sensor FS may be reduced, and thus,a touch force level may be sensed by using a touch force levelcalculation algorithm which models a voltage variation rate with respectto a resistance reduction rate of the force sensor FS, based on thetouch force of the user.

The pressure reaction member 550 may act as a haptic output device in ahaptic mode. That is, as described above, the haptic mode according toan embodiment may include a vibration haptic mode based on a vibrationof the pressure reaction member 550 and an electrostatic haptic modebased on an electrostatic force of the pressure reaction member 550.

The first touch electrode layer 510 according to the present embodimentmay include a plurality of secondary electrodes SE1 and SE2 which areprovided along with the plurality of second touch electrodes TE2 and aredisposed adjacent to at least one of one side TE2 a and the other sideTE2 b of each of the plurality of second touch electrodes TE2.

The first touch electrode layer 510 according to the present embodimentmay include a plurality of first secondary electrodes SE1, which areprovided adjacent to and in parallel with the one side TE2 a of each ofthe second touch electrodes TE2, and a plurality of second secondaryelectrodes SE2 which are provided adjacent to and in parallel with theother side TE2 b of each of the second touch electrodes TE2. Each of theplurality of first and second secondary electrodes SE1 and SE2 may havea shape which is the same as that of each of the second touch electrodesTE2.

Each of the plurality of first secondary electrodes SE1 may be connectedto the touch driving circuit 900 through a corresponding first secondaryrouting line among a plurality of first secondary routing lines SRL1,and each of the plurality of second secondary electrodes SE2 may beconnected to the touch driving circuit 900 through a correspondingsecond secondary routing line among a plurality of second secondaryrouting lines SRL2. Each of the plurality of first and second secondaryelectrodes SE1 and SE2 may be floated by the touch driving circuit 900or may be electrically connected to the second touch electrode TE2 orthe second routing line RL2 adjacent thereto.

In detail, a mutual capacitance of the touch sensor TS provided theelectrode insulation layer 515 between the first touch electrode TE1 andthe second touch electrode TE2 intersecting each other may be reduced asan area of the second touch electrode TE2 overlapping the first touchelectrode TE1 is enlarged, and thus, it is difficult to sense a touchposition of a user. Accordingly, the plurality of first secondaryelectrodes SE1 and the plurality of second secondary electrodes SE2 maydecrease an area of the second touch electrode TE2 overlapping the firsttouch electrode TE1 during the first touch sensing period, and thus, maybe electrically floated for effectively providing the mutual capacitanceof the touch sensor TS.

On the other hand, a voltage or a resistance of the force sensor FSprovided in the pressure reaction member 550 between the third touchelectrode TE3 and the second touch electrode TE2 intersecting each othermay increase as an overlapping area between the first touch electrodeTE1 and the second touch electrode TE2 is enlarged, with respect to thesame pressure. Accordingly, the plurality of first secondary electrodesSE1 and the plurality of second secondary electrodes SE2 may beelectrically connected to the second touch electrode TE adjacent theretoduring the second touch sensing period, and thus, an overlapping areabetween the second touch electrode TE2 and the third touch electrode TE3may be enlarged, thereby enhancing an efficiency of touch force sensing.

The plurality of first secondary electrodes SE1 and the plurality ofsecond secondary electrodes SE2 may be used as a touch force sensingelectrode for sensing a touch force and may be used as a floatingelectrode which enables a touch position to be sensed.

Moreover, one side of each of the first and second secondary electrodesSE1 and SE2 may be electrically connected to each other by a connectionsecondary electrode SE3.

The connection secondary electrode SE3 may be spaced apart from one end(for example, one short side TE2 c) of the second touch electrode TE2and may be provided in parallel with the one short side TE2 c, andmoreover, the connection secondary electrode SE3 may electricallyconnect one ends of the first and second secondary electrodes SE1 andSE2 which are parallel to each other with an adjacent second touchelectrode TE2 therebetween. Therefore, the connection secondaryelectrode SE3 may connect one ends of the first and second secondaryelectrodes SE1 and SE2 which are adjacent to one side TE2 a and theother side TE2 b of the second touch electrode TE2. That is, each of theplurality of first second electrodes SE1 may be provided adjacent to oneside of a corresponding second touch electrode TE2. The connectionsecondary electrode SE3 may be provided in plurality. Each of theplurality of connection secondary electrodes SE3 may be spaced apartfrom the one short side TE2 c of the second touch electrode TE2 adjacentthereto, may be parallel to the one short side TE2 c, and may extendfrom one end of a corresponding first secondary electrode SE1. Also,each of the plurality of second secondary electrodes SE2 may be adjacentto the other side of a corresponding second touch electrode TE2 and mayextend from an end of a corresponding connection secondary electrodeSE3. Therefore, a plurality of secondary electrodes which include theplurality of first secondary electrodes SE1, the plurality of connectionsecondary electrodes SE3, and the plurality of second secondaryelectrodes SE2 may be electrically connected to each other, may beprovided on the same layer, and may have a ⊂-shape or a ⊃-shape, therebysurrounding sides of the second touch electrode TE2 other than the othershort side of the second touch electrode TE2. Here, the other short sideof the second touch electrode TE2 may be defined as a portion connectedto the secondary routing line SRL.

In addition, in FIG. 12, each of the plurality of first secondaryelectrodes SE1 and the plurality of second secondary electrodes SE2 isillustrated as having a bar shape, but is not limited thereto. In otherembodiments, in order to increase a transmittance of light emitted fromeach pixel SP, each of the plurality of first secondary electrodes SE1and the plurality of second secondary electrodes SE2 may be formed in aplurality of line structures, mesh structures, or trapezoid structureswhich are electrically connected to each other, or may include aplurality of openings which are arranged at certain intervals in a slitor lattice type.

In the organic light emitting display device according to the presentembodiment, the touch driving circuit 900 may be connected to theplurality of first touch electrodes TE1, the plurality of second touchelectrodes TE2, and the plurality of third touch electrodes TE3. Thatis, the touch driving circuit 900 may be connected to the plurality offirst touch electrodes TE1, the plurality of second touch electrodesTE2, and the plurality of third touch electrodes TE3 through theplurality of first to third routing lines RL1, RL2 and RL3 provided onthe substrate 10 in a one-to-one relationship and may be connected tothe plurality of first and second secondary electrodes SE1 and SE2through the plurality of first and second secondary routing lines SRL1and SRL2 provided on the substrate 10 in a one-to-one relationship.

The touch driving circuit 900 according to the present embodiment maytime-divisionally drive the touch sensing layer 500 in the first touchsensing period and the second touch sensing period in response to atouch mode signal supplied from a host control circuit, and in each ofthe first touch sensing period and the second touch sensing period, whena touch event occurs, the touch driving circuit 900 may drive the touchsensing layer 500 in a haptic mode.

During the first touch sensing period, as illustrated in FIG. 14A, thetouch driving circuit 900 may electrically float the plurality of thirdtouch electrodes TE3 and the plurality of first and second secondaryelectrodes SE1 and SE2, apply a first touch driving pulse TDP1 to atleast one of the plurality of first touch electrodes TE1, and sense amutual capacitance variation between the first and second touchelectrodes TE1 and TE2 caused by a user touch through the plurality ofsecond touch electrodes TE2 to generate a first touch sensing signal.For example, during the first touch sensing period, the touch drivingcircuit 900 may sequentially apply the first touch driving pulse TDP1 tothe plurality of first touch electrodes TE1 and may sense the mutualcapacitance variation of the touch sensor TS, provided between the firsttouch electrode TE1 to which the first touch driving pulse TDP1 isapplied and the second touch electrode TE2 overlapping the first touchelectrode TE1, through the plurality of second touch electrodes TE2 togenerate the first touch sensing signal.

During the second touch sensing period, as illustrated in FIG. 14B, thetouch driving circuit 900 may electrically float the plurality of firsttouch electrodes TE1, apply a second touch driving pulse TDP2 to atleast one of the plurality of third touch electrodes TE3, and sense avoltage variation of the force sensor FS, caused by a user touch,through the plurality of second touch electrodes TE2 to generate asecond touch sensing signal. For example, during the second touchsensing period, the touch driving circuit 900 may sequentially apply thesecond touch driving pulse TDP2 to the plurality of third touchelectrodes TE3 and may sense a voltage variation (or a resistancevariation) of the force sensor FS, provided between the third touchelectrode TE3 to which the second touch driving pulse TDP2 is appliedand the second touch electrode TE2 overlapping the third touch electrodeTE3, through the plurality of second touch electrodes TE2 to generatethe second touch sensing signal.

In addition, the touch driving circuit 900 may determine the presence ofa touch event to calculate a touch event area, based on the first touchsensing signal generated through sensing during the first touch sensingperiod, apply the second touch driving pulse TDP2 to at least one thirdtouch electrode TE3 provided in the touch event area during the secondtouch sensing period, and sense a voltage variation (or a resistancevariation) of the force sensor FS of the pressure reaction member 550,caused by a touch force of a user, through the plurality of second touchelectrodes TE2 to generate the second touch sensing signal.Subsequently, based on the second touch sensing signal, the touchdriving circuit 900 may calculate touch position coordinates to outputthe touch position coordinates to the host control circuit, or maycalculate a touch force level and touch position coordinates to outputthe touch force level and the touch position coordinates to the hostcontrol circuit. That is, in the present embodiment, during the secondtouch sensing period, touch force sensing may be locally performed on atouch event area which is calculated through sensing in the first touchsensing period, thereby shortening a touch force sensing time for whicha touch force of a user is sensed.

According to another embodiment, as illustrated in FIG. 14B, during thesecond touch sensing period, the touch driving circuit 900 mayelectrically float the plurality of first touch electrodes TE1, connecteach of the plurality of first and second secondary electrodes SE1 andSE2 to the second touch electrode TE2 adjacent thereto, apply the secondtouch driving pulse TDP2 to at least one of the plurality of third touchelectrodes TE3, and sense a voltage variation (or a resistancevariation) of the force sensor FS of the pressure reaction member 550,caused by a touch force of a user, through the plurality of second touchelectrodes TE2 to generate the second touch sensing signal. In thiscase, each of the plurality of second touch electrodes TE2 respectivelyoverlapping the plurality of third touch electrodes TE3 may beelectrically connected to the first and second secondary electrodes SE1and SE2 adjacent thereto, and thus, an overlapping area between thethird touch electrode TE3 and the second touch electrode TE2 increasesby an area of the first and second secondary electrodes SE1 and SE2.Therefore, a voltage (or a resistance) generated in the force sensor FSmay further vary by an area of the first and second secondary electrodesSE1 and SE2 connected to the second touch electrode TE2, and thus, inpresent embodiment, a voltage variation (or a resistance variation)occurring in the force sensor FS is more easily sensed.

In addition, since the pressure reaction member 550 is disposed betweenthe first touch electrode layer 510 and the second touch electrode layer530, the pressure reaction member 550 may act as a haptic output device.That is, the organic light emitting display device according to thepresent embodiment may realize the haptic mode by using the pressurereaction member 550. The haptic mode according to an embodiment mayinclude a vibration haptic mode based on a vibration of the pressurereaction member 550 and an electrostatic haptic mode based on anelectrostatic force of the pressure reaction member 550. The haptic modeis as described above, and thus, its detailed description is notrepeated.

As described above, since the touch sensing layer 500 is directlyprovided in the organic light emitting display panel, the organic lightemitting display device according to an embodiment has a thin thicknessdespite including the touch panel. The organic light emitting displaydevice may sense a capacitance variation caused by a user touch to sensea touch position by the user, and may sense a voltage or resistancevariation of the pressure reaction member 550 caused by a touch force ofthe user to sense a touch force of the user. Also, in the organic lightemitting display device according to an embodiment, the first and secondsecondary electrodes SE1 and SE2 may be connected to the second touchelectrode TE2 when sensing the touch force of the user, and thus, anarea of the second touch electrode TE2 overlapping the third touchelectrode TE3 increases, thereby increasing an efficiency of touch forcesensing.

Optionally, in the organic light emitting display device according tothe present embodiment, the plurality of first touch electrodes TE1 andthe plurality of third touch electrodes TE3 may be exchanged in theirdisposed positions. In this case, similarly to FIG. 11, the plurality ofthird touch electrodes TE3 directly provided on a top of theencapsulation layer 300 may be configured as one third touch electrodeTE3.

FIG. 15 is a cross-sectional view for describing an organic lightemitting display device according to another embodiment and isconfigured by adding a function layer to the organic light emittingdisplay device illustrated in FIG. 11. Similarly to the display layer110A in the embodiment shown in FIG. 2, the display layer 110F in thisembodiment shown in FIG. 15 includes the substrate 10, the pixel arraylayer 100, and the encapsulation layer 300. Therefore, only a functionlayer and elements relevant thereto will be described.

Referring to FIG. 15, in the organic light emitting display deviceaccording to the present embodiment, a function layer 520 may bedisposed between a touch sensing layer 500 and a cover window 700. Thefunction layer 520 is for preventing an organic light emitting device EDas well as the first touch electrode layer 510 from being damaged byexternal water or oxygen, and may have the same configuration as that ofthe function layer 520 illustrated in FIG. 8. Therefore, only aconfiguration and an arrangement structure of the function layer 520will be described.

The function layer 520 according to one or more embodiments may includea barrier film 522 disposed between the touch sensing layer 500 and thecover window 700.

The barrier film 522 according to an embodiment may be adhered to awhole top of the touch sensing layer 500 by a first transparent adhesive521 to cover the whole top of the touch sensing layer 500. In this case,a bottom of the barrier film 522 may be coupled to a second touchelectrode layer 530 of the touch sensing layer 500 by the firsttransparent adhesive 521, and a top of the barrier film 522 may bedirectly coupled to the cover window 700, namely, an optical adhesivemember 600.

According to one or more embodiments, the function layer 520 may includethe barrier film 522, disposed between the touch sensing layer 500 andthe cover window 700, and a light control film 524 disposed between thebarrier film 522 and the cover window 700.

The barrier film 522 may be disposed between the touch sensing layer 500and the light control film 524. That is, the barrier film 522 may beadhered to the whole top of the touch sensing layer 500 by the firsttransparent adhesive 521 to cover the whole top of the touch sensinglayer 500. In this case, the bottom of the barrier film 522 may beadhered to the second touch electrode layer 530 of the touch sensinglayer 500 by the first transparent adhesive 521, and the top of thebarrier film 522 may be directly coupled to a bottom of the lightcontrol film 524 by a second transparent adhesive 523.

The light control film 524 may be adhered to the top of the barrier film522 by the second transparent adhesive 523 to cover the whole top of thebarrier film 522. In this case, the bottom of the light control film 524may be adhered to the top of the barrier film 522 by the secondtransparent adhesive 523, and a top of the light control film 524 may bedirectly coupled to the cover window 700, namely, the optical adhesivemember 600. Also, the light control film 524 enhances the luminancecharacteristic of light emitted from each pixel SP. For example, thelight control film 524 may be a polarizing film that polarizes the lightemitted from each pixel SP.

In the function layer 520 according to various embodiments, the barrierfilm 522 may be formed by coating an inorganic insulating material on anorganic insulation film. The barrier film 522 is for primarilypreventing water or oxygen from penetrating into each pixel SP and maybe formed of a material which is low in water vapor transmission rate.Also, the barrier film 522 may act as a supporter that supports thebottom of the pressure reaction member 550 in order for a thickness ofthe pressure reaction member 550 to be modified based on a touch forceof a user. Also, the barrier film 522 may relax an impact which isapplied to the organic light emitting display device due to the touchforce of the user, thereby preventing an organic light emitting deviceED from being damaged by the impact and additionally preventing thetouch sensing layer 500 from being damaged by water or oxygen.

Since the organic light emitting display device according to the presentembodiment includes the barrier film 522, the organic light emittingdisplay device according to the present embodiment has the same effectsas those of the organic light emitting display device illustrated inFIG. 11, and moreover, the organic light emitting device ED as well asthe touch sensing layer 500 can be additionally prevented from beingdamaged by an impact and water or oxygen.

Optionally, in the organic light emitting display device according tothe present embodiment, the plurality of first touch electrodes TE1 andthe plurality of third touch electrodes TE3 may be exchanged in theirdisposed positions. In this case, similarly to FIG. 10, the plurality ofthird touch electrodes TE3 directly provided on a top of theencapsulation layer 300 may be configured as one third touch electrodeTE3.

FIG. 16 is a cross-sectional view for describing an organic lightemitting display device according to another embodiment and isconfigured by adding a black matrix, a color filter layer, and a bufferlayer to the organic light emitting display device illustrated in FIG.1.

Referring to FIG. 16, the organic light emitting display deviceaccording to the present embodiment may include (i) a display layer 110Gincluding a substrate 10, a pixel array layer 100, an encapsulationlayer 300, a black matrix 410, a color filter layer 430, and a bufferlayer 450, (ii) a touch sensing layer 500, (iii) an optical adhesivemember 600, (iv) a cover window 700, and (v) a touch driving circuit900.

Except that the organic light emitting device ED of each pixel SPprovided in the pixel array layer 100 emits white light in the organiclight emitting display device illustrated in FIG. 1, the substrate 10,the pixel array layer 100, and the encapsulation layer 300 are the sameas the illustration in FIG. 1, and thus, their detailed descriptions arenot repeated.

The black matrix 410 may define an opening area of each pixel SPprovided on the substrate 10. That is, the black matrix 410 may bedirectly provided on the encapsulation layer 300 overlapping a lightblocking area other than an opening area overlapping an organic lightemitting device ED of each pixel SP, thereby preventing color mixturebetween adjacent opening areas. The black matrix 410 according to anembodiment may include a plurality of first light blocking patternswhich cover a plurality of gate lines and a pixel circuit PC of eachpixel SP, a plurality of second light blocking patterns which cover aplurality of data lines and a plurality of pixel driving power lines,and a third blocking pattern which covers an edge of the encapsulationlayer 300.

The color filter layer 430 may be directly provided on a top of theencapsulation layer 300 overlapping the opening area defined by theblack matrix 410 and may include a red color filter, a green colorfilter, and a blue color filter which respectively correspond to colorsrespectively defined in the plurality pixels SP. The color filter layer430 may transmit only light, having a wavelength of a colorcorresponding to a certain pixel SP, in white light emitted from thecertain pixel SP.

The buffer layer 450 may cover the black matrix 410 and the color filterlayer 430. The buffer layer 450 may provide a planar surface on theblack matrix 410 and the color filter layer 430.

Except that a plurality of first touch electrodes TE1 and a plurality ofsecond touch electrodes TE2 included in the first touch electrode layer510 are directly coupled to the top of the buffer layer 450, the touchsensing layer 500 may have the same configuration as that of the touchsensing layer illustrated in FIGS. 1 to 3, and thus, its detaileddescription is not repeated.

In addition, the buffer layer 450 may support the touch sensing layer500 and may protect the color filter layer 430 in a process ofmanufacturing the touch sensing layer 500. The buffer layer 450according to an embodiment may be formed to have a thickness between 500Å and 5 μm, and may maintain, as a minimum of 5 μm, a separationdistance between a cathode electrode CE and each of the electrodes TE1and TE2 of the first touch electrode layer 510 of the touch sensinglayer 500. Therefore, in the present embodiment, a parasitic capacitancegenerated between the cathode electrode CE and each of the electrodesTE1 and TE2 of the first touch electrode layer 510 is minimized, therebypreventing a mutual influence caused by coupling between the cathodeelectrode CE and each of the electrodes TE1 and TE2 of the first touchelectrode layer 510. If the separation distance between the cathodeelectrode CE and each of the electrodes TE1 and TE2 of the first touchelectrode layer 510 is less than 5 μm, touch performance can be degradeddue to the mutual influence caused by the coupling.

Moreover, the buffer layer 450 prevents a chemical solution (adeveloping solution, an etching solution, etc.) used in a process ofmanufacturing the touch sensing layer 500, external water, and/or thelike from penetrating into the organic light emitting device ED, therebypreventing damage of the organic light emitting device ED. The bufferlayer 450 may be formed at a low temperature of 100 C.° or less so as toprevent damage of the organic light emitting device ED vulnerable to ahigh temperature and may be formed of an organic insulating materialhaving a low dielectric constant of 1 to 3. For example, the bufferlayer 450 may include an acryl-based material, an epoxy-based material,or a siloxane-based material. The buffer layer 450 including an organicinsulating material may have a planarization function, therebypreventing a crack from occurring in the electrodes of the touch sensinglayer 500 and the encapsulation layer 300 when bending the organic lightemitting display device.

Except that the plurality of first touch electrodes TE1 and theplurality of second touch electrodes TE2 included in the first touchelectrode layer 510 are directly coupled to the top of the buffer layer450, the touch sensing layer 500 has the same configuration as that ofthe touch sensing layer illustrated in FIGS. 1 to 3, and thus, itsdetailed description is not provided.

The cover window 700 may be coupled to a top of the touch sensing layer500 by the optical adhesive member 600. The cover window 700 is the sameas the cover window illustrated in FIGS. 1 to 3, and thus, its detaileddescription is not repeated.

The touch driving circuit 900 may be connected to the plurality of firsttouch electrodes TE1, the plurality of second touch electrodes TE2, andthe plurality of third touch electrodes TE3. That is, the touch drivingcircuit 900 has the same configuration as that of the touch drivingcircuit illustrated in FIG. 2, and thus, its detailed description is notrepeated.

In addition, the organic light emitting display device according to thepresent embodiment may further include a function layer disposed betweenthe touch sensing layer 500 and the cover window 700. The function layerhas the same configuration as that of the function layer 520 illustratedin FIG. 8, and thus, its detailed description is not repeated.

Optionally, each of the first touch electrode layer 510 and the secondtouch electrode layer 530 may be provided in plurality, and theplurality of first touch electrode layers 510 and second touch electrodelayers 530 may be exchanged in their disposed positions. That is, thefirst touch electrode layer 510 may include the plurality of third touchelectrodes TE3 directly provided on the top of the buffer layer 450, andthe second touch electrode layer 530 may include the plurality of firsttouch electrodes TE1 and the plurality of second touch electrodes TE2directly provided on a top of the pressure reaction member 550. Here,similarly to FIG. 10, the plurality of third touch electrodes TE3directly provided on the top of the buffer layer 450 may be configuredas one third touch electrode TE3.

The organic light emitting display device according to the presentembodiment provides the same effects as those of the organic lightemitting display device illustrated in FIGS. 1 to 5B, and the organiclight emitting devices ED of respective pixels SP may be configured inthe same structure. Accordingly, a manufacturing process is simplified,and the organic light emitting devices ED are prevented from beingdamaged by the buffer layer 450 in a process of manufacturing the touchsensing layer 500.

FIG. 17 is a cross-sectional view for describing an organic lightemitting display device according to another embodiment and isconfigured by adding a black matrix, a color filter layer, and a bufferlayer to the organic light emitting display device illustrated in FIG.11.

Referring to FIG. 17, the organic light emitting display deviceaccording to the present embodiment may include (i) a display layer 100Hincluding a substrate 10, a pixel array layer 100, an encapsulationlayer 300, a black matrix 410, a color filter layer 430, and a bufferlayer 450, (ii) a touch sensing layer 500, (iii) an optical adhesivemember 600, (iv) a cover window 700, and (v) a touch driving circuit900.

Except that the organic light emitting device ED of each pixel SPprovided in the pixel array layer 100 emits white light in the organiclight emitting display device illustrated in FIG. 12, the substrate 10,the pixel array layer 100, and the encapsulation layer 300 are the sameas the illustration in FIG. 12, and thus, their detailed descriptionsare not repeated.

The black matrix 410, the color filter layer 430, and the buffer layer450 may be provided between the encapsulation layer 300 and the touchsensing layer 500 and are the same as the illustration in FIG. 16, andthus, their detailed descriptions are not repeated.

The touch sensing layer 500 may be directly provided on a top of thebuffer layer 450. Except that the touch sensing layer 500 is directlyprovided on the top of the buffer layer 450, the touch sensing layer 500may have the same configuration as that of the touch sensing layerillustrated in FIGS. 11 to 13, and thus, its detailed description is notrepeated.

The cover window 700 may be coupled to a top of the touch sensing layer500 by the optical adhesive member 600 and may include a second touchelectrode layer 530 of the touch sensing layer 500. The cover window 700is the same as the cover window illustrated in FIGS. 1 to 3, and thus,its detailed description is not repeated.

The touch driving circuit 900 may be connected to a plurality of firsttouch electrodes TE1, a plurality of second touch electrodes TE2, and aplurality of third touch electrodes TE3. That is, the touch drivingcircuit 900 has the same configuration as that of the touch drivingcircuit illustrated in FIG. 2, and thus, its detailed description is notrepeated.

In addition, the organic light emitting display device according to thepresent embodiment may further include a function layer disposed betweenthe touch sensing layer 500 and the cover window 700. The function layerhas the same configuration as that of the function layer 520 illustratedin FIG. 15, and thus, its detailed description is not repeated.

Optionally, the plurality of first touch electrodes TE1 and theplurality of third touch electrodes TE3 may be exchanged in theirdisposed positions. In this case, similarly to FIG. 10, the plurality ofthird touch electrodes TE3 directly provided on the top of the bufferlayer 450 may be configured as one third touch electrode TE3.

FIG. 18 is a flowchart for describing a touch sensing method performedby an organic light emitting display device according to an embodiment.

The touch sensing method performed by the organic light emitting displaydevice according to an embodiment will be described in detail withreference to FIGS. 18 and 1 to 8.

First, in operation S100, the touch driving circuit 900 may perform thetouch position sensing during the first touch sensing period. In detail,during the first touch sensing period, as illustrated in FIG. 5A, thetouch driving circuit 900 may electrically float the plurality of thirdtouch electrodes TE3 and the plurality of first and second secondaryelectrodes SE1 and SE2, apply the first touch driving pulse TDP1 to atleast one of the plurality of first touch electrodes TE1, and sense amutual capacitance variation, caused by a touch of a user, of the touchsensor TS provided in the pressure reaction member 550 between the firsttouch electrode TE1 and the second touch electrode TE2, through theplurality of second touch electrodes TE2 to generate the first touchsensing signal.

Subsequently, in operation S200, the touch driving circuit 900 maydetermine whether a touch event occurs, based on the first touch sensingsignal generated through sensing during the first touch sensing period.

When the touch event does not occur (“NO” at S200) in operation S200,the touch driving circuit 900 may again perform the touch positionsensing in operation S100.

When the touch event occurs (“YES” at S200) in operation S200, the touchdriving circuit 900 may calculate a touch event area, based on the firsttouch sensing signal and may perform a touch force local sensing duringthe second touch sensing period, based on the touch event area inoperation S300. In detail, as illustrated in FIG. 5B, during the secondtouch sensing period, the touch driving circuit 900 may electricallyfloat the plurality of first touch electrodes TE1, electrically connecteach of the plurality of first and second secondary electrodes SE1 andSE2 to the third touch electrode TE3 adjacent thereto, apply the secondtouch driving pulse TDP2 to at least one third touch electrode TE3provided in the touch event area, and sense a voltage variation (or aresistance variation), caused by a touch force of a user, of the forcesensor FS, provided in the pressure reaction member 550 between thesecond touch electrode TE2 and the third touch electrode TE3, throughthe plurality of second touch electrodes TE2 to generate the secondtouch sensing signal.

Subsequently, in operation S400, the touch driving circuit 900 maydetermine whether a touch force is sensed, based on the second touchsensing signal generated through sensing during the second touch sensingperiod.

When the touch force is sensed in the touch event area (“YES” at S400)in operation S400, the touch driving circuit 900 may calculate touchposition coordinates corresponding to the touch event area and a touchforce level based on the second touch sensing signal and may supply thetouch position coordinates and the touch force level to the host controlcircuit in operation S500. Therefore, the host control circuit mayexecute an application which corresponds to the touch positioncoordinates and the touch force level supplied from the touch drivingcircuit 900.

When the touch force is not sensed in the touch event area (“NO” atS400) in operation S400, the touch driving circuit 900 may calculatetouch position coordinates corresponding to the touch event area and maysupply the touch position coordinates to the host control circuit inoperation S600. Therefore, the host control circuit may execute anapplication corresponding to the touch position coordinates suppliedfrom the touch driving circuit 900.

The touch sensing method performed by the organic light emitting displaydevice according to an embodiment will be described in detail withreference to FIGS. 18 and 11 to 17.

First, in operation S100, the touch driving circuit 900 may perform thetouch position sensing during the first touch sensing period. In detail,during the first touch sensing period, as illustrated in FIG. 14A, thetouch driving circuit 900 may electrically float the plurality of thirdtouch electrodes TE3 and the plurality of first and second secondaryelectrodes SE1 and SE2, apply the first touch driving pulse TDP1 to atleast one of the plurality of first touch electrodes TE1, and sense amutual capacitance variation, caused by a touch of a user, of the touchsensor TS provided in the pressure reaction member 550 between the firsttouch electrode TE1 and the second touch electrode TE2, through theplurality of second touch electrodes TE2 to generate the first touchsensing signal.

Subsequently, in operation S200, the touch driving circuit 900 maydetermine whether a touch event occurs, based on the first touch sensingsignal generated through sensing during the first touch sensing period.

When the touch event does not occur (“NO” at S200) in operation S200,the touch driving circuit 900 may again perform the touch positionsensing in operation S100.

When the touch event occurs (“YES” at S200) in operation S200, the touchdriving circuit 900 may calculate a touch event area, based on the firsttouch sensing signal and may perform a touch force local sensing duringthe second touch sensing period, based on the touch event area inoperation S300. In detail, as illustrated in FIG. 14B, during the secondtouch sensing period, the touch driving circuit 900 may electricallyfloat the plurality of first touch electrodes TE1, connect each of theplurality of first and second secondary electrodes SE1 and SE2 to thesecond touch electrode TE2 adjacent thereto, apply the second touchdriving pulse TDP2 to at least one of the plurality of third touchelectrodes TE3 provided in the touch event area, and sense a voltagevariation (or a resistance variation), caused by a touch force of auser, of the force sensor FS provided in the pressure reaction member550 between the second touch electrode TE2 and the third touch electrodeTE3, through the plurality of second touch electrodes TE2 to generatethe second touch sensing signal.

Subsequently, in operation S400, the touch driving circuit 900 maydetermine whether a touch force is sensed, by using a touch positioncalculation algorithm based on the second touch sensing signal generatedthrough sensing during the second touch sensing period.

When the touch force is sensed in the touch event area (“YES” at S400)in operation S400, the touch driving circuit 900 may calculate touchposition coordinates corresponding to the touch event area and a touchforce level by using a touch force level calculation algorithm based onthe second touch sensing signal and may supply the touch positioncoordinates and the touch force level to the host control circuit inoperation S500. Therefore, the host control circuit may execute anapplication which corresponds to the touch position coordinates and thetouch force level supplied from the touch driving circuit 900.

When the touch force is not sensed in the touch event area (“NO” atS400) in operation S400, the touch driving circuit 900 may calculatetouch position coordinates corresponding to the touch event area and maysupply the touch position coordinates to the host control circuit inoperation S600. Therefore, the host control circuit may execute anapplication corresponding to the touch position coordinates suppliedfrom the touch driving circuit 900.

The organic light emitting display device according to the embodimentsmay be used as a display screen of one of an electronic notebook, ane-book, a portable multimedia player (PMP), a navigation device, anultra-mobile personal computer (UMPC), a mobile phone, a smartwatch, atablet PC, a watch phone, a wearable device, a mobile communicationterminal, a televisions (TV), a notebook computer, and a monitor.

As described above, the organic light emitting display device accordingto the embodiments may include a touch panel and may have a thinthickness. Also, the organic light emitting display device according tothe embodiments may sense a touch position and a touch force, therebyincreasing an efficiency of touch force sensing.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the present inventionwithout departing from the spirit or scope of the inventions. Thus, itis intended that the present invention covers the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

What is claimed is:
 1. An organic light emitting display devicecomprising: a display layer comprising: a substrate, a pixel array layeron the substrate, the pixel array layer including a plurality of pixels,each of the plurality of pixels including a thin film transistor (TFT)and an organic light emitting diode, and an encapsulation layer coveringthe pixel array layer; a cover window; and a touch sensing layerdirectly disposed on the display layer, the touch sensing layer disposedbetween the display layer and the cover window, the touch sensing layercomprising: a first touch electrode layer directly on the display layer,a second touch electrode layer between the first touch electrode layerand the cover window, and a pressure reaction member between the firsttouch electrode layer and the second touch electrode layer, wherein theelectrical characteristic of the pressure reaction member changesaccording to force applied to the pressure reaction member, wherein thesecond touch electrode layer further comprises a plurality of thirdtouch electrodes disposed on the pressure reaction member and aplurality of first secondary electrodes and a plurality of secondsecondary electrodes disposed along the plurality of third touchelectrodes, each of the plurality of third touch electrodes disposedbetween an adjacent one of the first secondary electrodes and anadjacent one of the second secondary electrodes, wherein the pluralityof third touch electrodes, the plurality of first secondary electrodes,and the plurality of second secondary electrodes are electricallyfloated during a touch position sensing period, and wherein each of theplurality of third touch electrodes is electrically connected to theadjacent one of the first secondary electrodes and the adjacent one ofthe second secondary electrodes during a touch force sensing period. 2.The organic light emitting display device of claim 1, furthercomprising: a touch driving circuit configured to determine force of atouch on the cover window according to a change in the electricalcharacteristic of the pressure reaction member associated with thetouch, wherein the change in the electrical characteristic of thepressure reaction member is a change in a capacitance of the pressurereaction member or a change in a resistance of the pressure reactionmember.
 3. The organic light emitting display device of claim 1, whereinthe pressure reaction member comprises a piezoelectric material or apiezoresistive material.
 4. The organic light emitting display device ofclaim 3, wherein the piezoelectric material comprises at least one oflead zirconate titanate (PZT), BaTiO₃, polyvinylidene difluoride (PVDF),and parylene-C.
 5. The organic light emitting display device of claim 3,wherein the piezoresistive material comprises a polymer and a conductivefiller.
 6. The organic light emitting display device of claim 5, whereinthe conductive filler comprises at least one of nickel (Ni), copper(Cu), silver (Ag), aluminum (Al), iron (Fe), vanadium oxide (V₂O₃),titanium oxide (TiO), carbon black, graphite, graphene, and carbon nanotube (CNT).
 7. The organic light emitting display device of claim 1,wherein the display layer further comprises a barrier film disposedbetween the encapsulation layer and the first touch electrode layer,wherein the first touch electrode layer comprises a plurality of firsttouch electrodes and a plurality of second touch electrodes directly onthe barrier film, and wherein the second touch electrode layer comprisesa plurality of third touch electrodes disposed on the pressure reactionmember.
 8. The organic light emitting display device of claim 1, whereinthe display layer further comprises: a light control film disposedbetween the encapsulation layer and the first touch electrode layer,wherein the first touch electrode layer comprises a plurality of firsttouch electrodes and a plurality of second touch electrodes directly onthe light control film, and wherein the second touch electrode layercomprises a plurality of third touch electrodes disposed on the pressurereaction member.
 9. An organic light emitting display device comprising:a display layer; a cover window; and a touch sensing layer directlydisposed on the display layer, the touch sensing layer disposed betweenthe display layer and the cover window, the touch sensing layercomprising: a first touch electrode layer directly on the display layer,a second touch electrode layer between the first touch electrode layerand the cover window, and a pressure reaction member between the firsttouch electrode layer and the second touch electrode layer, electricalcharacteristic of the pressure reaction member changed according toforce applied to the pressure reaction member, wherein the display layercomprises: a substrate; a pixel array layer on the substrate, the pixelarray layer including a plurality of pixels, each of the plurality ofpixels including a thin film transistor (TFT) and an organic lightemitting diode; an encapsulation layer covering the pixel array layer; ablack matrix directly on the encapsulation layer, the black matrixdefining an opening area of each of the plurality of pixels; a colorfilter layer disposed in the opening area of each of the plurality ofpixels; and a buffer layer covering the black matrix and the colorfilter layer, wherein the first touch electrode layer comprises aplurality of first touch electrodes and a plurality of second touchelectrodes directly on the buffer layer, and wherein the second touchelectrode layer comprises a plurality of third touch electrodes directlyon the pressure reaction member.
 10. The organic light emitting displaydevice of claim 1, wherein the first touch electrode layer comprises aplurality of first touch electrodes and a plurality of second touchelectrodes directly on the display layer.
 11. The organic light emittingdisplay device of claim 10, wherein the plurality of first touchelectrodes, the plurality of second touch electrodes, and the pluralityof third touch electrodes each comprise an amorphous transparentconductive material.
 12. The organic light emitting display device ofclaim 9, wherein the second touch electrode layer further comprises aplurality of first secondary electrodes and a plurality of secondsecondary electrodes disposed along the plurality of third touchelectrodes, each of the plurality of third touch electrodes disposedbetween an adjacent one of the first secondary electrodes and anadjacent one of the second secondary electrodes, wherein the pluralityof third touch electrodes, the plurality of first secondary electrodes,and the plurality of second secondary electrodes are electricallyfloated during a touch position sensing period, and wherein each of theplurality of third touch electrodes is electrically connected to theadjacent one of the first secondary electrodes and the adjacent one ofthe second secondary electrodes during a touch force sensing period. 13.The organic light emitting display device of claim 1, furthercomprising: a touch driving circuit connected to the plurality of firsttouch electrodes, the plurality of second touch electrodes, and theplurality of third touch electrodes, wherein, during the touch positionsensing period, the touch driving circuit applies a first touch drivingpulse to at least one of the first touch electrodes, senses a firsttouch sensing signal responsive to the first touch driving pulse throughthe plurality of second touch electrodes, and determines a touch eventarea corresponding to a touch on the cover window according to the firsttouch sensing signal, and wherein, during the touch force sensingperiod, the touch driving circuit applies a second touch driving pulseto at least one of the third touch electrodes disposed in the touchevent area, senses a second touch sensing signal responsive to thesecond touch driving pulse through the plurality of second touchelectrodes, and determines a touch force level and a touch positioncoordinate of the touch according to the second touch sensing signal.14. The organic light emitting display device of claim 13, wherein thesecond touch electrode layer further comprises a plurality of connectionelectrodes, each of the plurality of connection electrodes facing oneend of a corresponding one of the third touch electrodes andelectrically connecting one end of a corresponding one of the firstsecondary electrodes to one end of a corresponding one of the secondsecondary electrodes adjacent to the one of the third touch electrodes.15. An organic light emitting display device comprising: a display layercomprising: a substrate, a pixel array layer on the substrate, the pixelarray layer including a plurality of pixels, each of the plurality ofpixels including a thin film transistor (TFT) and an organic lightemitting diode, and an encapsulation layer covering the pixel arraylayer; a cover window; and a touch sensing layer directly disposed onthe display layer, the touch sensing layer disposed between the displaylayer and the cover window, the touch sensing layer comprising: a firsttouch electrode layer directly on the display layer, a second touchelectrode layer between the first touch electrode layer and the coverwindow, and a pressure reaction member between the first touch electrodelayer and the second touch electrode layer, wherein the electricalcharacteristic of the pressure reaction member changes according toforce applied to the pressure reaction member, wherein the first touchelectrode layer comprises: a plurality of first touch electrodesdirectly on the encapsulation layer, an electrode insulation layerdisposed on the encapsulation layer, the electrode insulation layercovering the plurality of first touch electrodes, and a plurality ofsecond touch electrodes directly on the electrode insulation layer, theplurality of second touch electrodes intersecting the plurality of firsttouch electrodes, and wherein the second touch electrode layer comprisesa plurality of third touch electrodes directly disposed on the pressurereaction member, wherein the first touch electrode layer furthercomprises a plurality of first secondary electrodes and a plurality ofsecond secondary electrodes disposed along the plurality of second touchelectrodes, each of the plurality of second touch electrodes disposedbetween an adjacent one of the first secondary electrodes and anadjacent one of the second secondary electrodes, wherein the pluralityof third touch electrodes, the plurality of first secondary electrodes,and the plurality of second secondary electrodes are electricallyfloated during a touch position sensing period, and wherein each of theplurality of second touch electrodes is electrically connected to theadjacent one of the first secondary electrodes and the adjacent one ofthe second secondary electrodes during a touch force sensing period. 16.The organic light emitting display device of claim 15, furthercomprising: a touch driving circuit connected to the plurality of firsttouch electrodes, the plurality of second touch electrodes, and theplurality of third touch electrodes, wherein, during the touch positionsensing period, the touch driving circuit applies a first touch drivingpulse to at least one first touch electrode, senses a first touchsensing signal responsive to the first touch driving pulse through theplurality of second touch electrodes, and determines a touch event areacorresponding to a touch on the cover window according to the firsttouch sensing signal, and wherein, during the touch force sensingperiod, the touch driving circuit applies a second touch driving pulseto at least one of the third touch electrodes disposed in the touchevent area, senses a second touch sensing signal responsive to thesecond touch driving pulse through (i) the plurality of second touchelectrodes, (ii) the first secondary electrodes, and (iii) the secondsecondary electrodes, and determines a touch force level and a touchposition coordinate of the touch according to the second touch sensingsignal.
 17. The organic light emitting display device of claim 16,wherein the first touch electrode layer further comprises a plurality ofconnection electrodes, each of the plurality of connection electrodesfacing one end of a corresponding one of the second touch electrodes andelectrically connecting one end of a corresponding one of the firstsecondary electrodes to one end of a corresponding one of the secondsecondary electrodes adjacent to the corresponding one of the secondtouch electrodes.
 18. An organic light emitting display devicecomprising: a display layer; a cover window; and a touch sensing layerdirectly disposed on the display layer, the touch sensing layer disposedbetween the display layer and the cover window, wherein the displaylayer comprise: a substrate; a pixel array layer on the substrate, thepixel array layer including a plurality of pixels, each of the pluralityof pixels including a thin film transistor (TFT) and an organic lightemitting diode; an encapsulation layer covering the pixel array layer; ablack matrix directly on the encapsulation layer, the black matrixdefining an opening area of each of the plurality of pixels; a colorfilter layer disposed in the opening area of each of the plurality ofpixels; and a buffer layer covering the black matrix and the colorfilter layer, wherein the touch sensing layer comprise: a first touchelectrode layer directly on the buffer layer; a second touch electrodelayer between the first touch electrode layer and the cover window; anda pressure reaction member between the first touch electrode layer andthe second touch electrode layer, electrical characteristic of thepressure reaction member changed according to force applied to thepressure reaction member, wherein the second touch electrode layercomprises a plurality of first touch electrodes and a plurality ofsecond touch electrodes directly on the pressure reaction member, andwherein the first touch electrode layer comprises a third touchelectrode directly on the buffer layer and overlapping with all of theplurality of first and second touch electrodes.
 19. The organic lightemitting display device of claim 15, wherein the display layer furthercomprises: a black matrix directly on the encapsulation layer, the blackmatrix defining an opening area of each of the plurality of pixels; acolor filter layer disposed in the opening area of each of the pluralityof pixels; and a buffer layer covering the black matrix and the colorfilter layer; wherein the first touch electrode layer is disposed on thebuffer layer.
 20. The organic light emitting display device of claim 9,wherein the pressure reaction member comprises a piezoelectric materialor a piezoresistive material.